Memoirs MCZ 4502

/IDemolrs of tbe /iDuseum of Comparative ZooIoqv AT HARVARD COLLEGE Vol XLV No 80LEN0GASTRES FROM THE EASTERN COAST OF NORTH AMERICA By HAROLD HEATH WITH FOURTEEN PLATES Published liy Permiasion of E Lester Jones, Superintendcnl U S Coast and Geodetic Survey and of H U S Commissioner of Fish and Fisheries] CAMBRIDGE, U S A.: IprtnteO for tbe flDuseum October, 1918 M Smith, TABLE OF CONTENTS Page Pace INTRODUCTION 187 CLASSIFICATION 189 Chaetoderma caudatum C vadorum 189 C lucidum 198 Chaetodermatidae 189 C bacillmn 201 Chaetoderma Neomeniidae 190 C 204 Aplacophora 191 Neomenia 192 192 192 193 Dorymenia Dondersiidae Nierstrassia Chaetoderma nitidulum squamosum 206 215 191 191 Strophomenia DESCRIPTION OF SPECIES 195 Neomenia verrilU Proneomenia acuminata 191 Proneomeniidae Proneomenia 193 193 193 Dorymenia peroneopsis 222 Strophomenia agassizi 229 Nierstrassia fragile 235 240 EMBRYOLOGY GENERAL CONSIDERATIONS ' BIBLIOGRAPHY EXPLANATION OF PLATES 251 261 203 SOLENOGASTRES FROM THE EASTERN COAST OF NORTH AMERICA INTRODUCTION The present report deals with a collection of upwards of one hundred and twenty-five Solenogastres dredged at various times by Coast Survey or U S Fish Commission vessels along the eastern coast of the United States The greater number of these were placed at my disposal by the Mr late Alexander Agassiz, who generously granted permission to include the descriptions of additional species based A E Verrill and by the The upon material kindly forwarded by officials of the National Prof Museum single station off embraced by these explorations, with the exception of a the south coast of Florida, another in the Gulf of St Lawrence and a third the coast of Newfoundland, extends from the Gulf of territory off on the north to the mouth of ber of dredge hauls were made along Chesapeake Bay on the south thirty-four were at depths ranging The larger from one hundred to five hundred fathoms, two from one thousand to fifteen hundred fathoms and one from seventeen hundred and fathoms The appended A num- shore in comparatively shallow water; three were from five hundred to one thousand fathoms, The Maine fifty-three table indicates the habitat \vith greater exactness following abbreviations have been employed to indicate the vessels engaged Albatross, Species B Bache, Be Blake, Bt Bluelight, Fk Fishhawk, Sp Speedwell : INTRODUCTION 188 Species CLASSIFICATION 189 CLASSIFICATION Judging from the material already is it descriljod, is evident that not only the genus Chaetoderma very widely distributed, but the individual species we are difficult to differentiate, especially where upon descriptions and Externally and internally there figures variation within a given species, to discover The are compelled to rely solely is considerable and suitable diagnostic characters are relations of the gut to the somatic musculature difficult and the ventral blood sinus at the junction of the pro- and metathorax are of considerable value in the specimens I have thus far others of characteristic sections examined, and with figures of this region and it is believed that it wiU be great difficulty, to recognize the species described in this Ocean and the earlier Pacific report The validity of the genus Dorymenia Heath has been questioned by investigators, but the discovery of a second species, with istic without possible, features of the first {Dorymenia all of certain the character- acuta), indicates that the genus was well founded Order Aplacophoea v Ihering Suborder I Chaetodermatina Simroth Spiculose integument continuous Chaetodermatidae, Suborder II all around the body p 189 Neomeniina Simroth Spiculose integument interrupted beneath by a longitudinal ven- tral furrow Neomeniidae, p 191 Proneomeniidae, p 191 Dondersiidae, p 192 CHAETODERMATIDAE Opening of mouth and sharply marked regions oped plume-like gills Simroth anal chamber terminal Body with more Ventral furrow and fold lacking Radula large unpaired cuticular tooth Two or less highly devel- distichous, polyserial or strongly reduced to a The mid-gut possesses, in most cases, a well- CHAETODERMA 190 developed remain separate Copulatory apparatus lacking gland digestive Cuticle spicules thin, often flat, Coelomoducts but needle-form, solid Inhabit bottom ooze CHAETODERMA Body vermiform, without minal of C Two mouth and ventral groove; chamber anal Radula reduced to conical peg Sexes separate gills Loven, 1845 ter- Type genus nitidulum Loven Head, cylindrical or pear-shaped, bounded posteriorly by a circular groove North Atlantic Spines with keel absent or but slightly developed C sp nov caudatum, Length from thickness of 3.3 in body mm of 428-499 fathoms, C vadorum, sp to 7.75 by 1.3 (p 193) mm by 1.1 thickness of 0.1 to 0.14 nuTi in length Body Maine sp Mouth by 1.45 mm metathorax and abdomen measure preabdomen to 15.2 occupies a cleft in the buccal plate at a depth of 25-95 fathoms, (p 195) nov size variable, mm mdth by mm 25 ranging from 1.2 Off coast of New mm width by 11.25 length to 0.75 Spines with keel sUght or undeveloped, with length average length on preabdomen of 0.12 buccal plate Greatest Northeast coast of the United States at a depth Spines strongly keeled and at junction of C lucidum, greatest diameter nov Length 12.5 Off coast of mm preabdomen; the postabdominal region narrows abruptly to a tail-Uke appendage from (p 193) mm Mouth occupies a cleft in the Jersey at 428-479 fathoms depth, (p 198) C bacillum, sp nov Length 11-17 mm length by 0.9-1.07 mm greatest diameter Spines moderately keeled with a length of 0.11-0.16 imn at the junction of the pro- and metathorax Mouth perforates the buccal plate coast at a depth of 900 fathoms, C squamosum, sp Length 25.7 the buccal plate at Off the Massachusetts (p 201) nov mm length by 1.3 mm greatest thickness Spines unusually thin, weakly keeled 1,234 fathoms depth, (p 204) Mouth pierces Off Massachusetts PRONEOMENIA NEOMENIIDAE Body compressed, more Index at most Opening 191 Simuoth or less crescent-shaped, without distinct divisions of atrium ventral, of the anal chamber ventral or Ventral furrow present, usually with several folds terminal times comparatively thick, spines mostly needle-like, A circlet of gills in the anal Epidermal lacking grooved or hollow Radula and salivary glands usually chamber Fore gut papillae, of simple structure, usually present protrusible, coelomoducts separate or united to organ flat, Cuticle some- Digestive gland lacking form a shell gland or copulatory Penial spines usual present Free, creeping about over bottom NEOMENIA Body anterior thick-set TuLLBERCi, 1875 and usually compressed and posterior ends laterally, similarly shaped 2-3 cm with long, Cloacal opening subterminal Ventral fold present with the groove extending to the cloacal chamber ules needle- or spearhead-shaped, projecting papillae present N Type of genus, N Broad stalked cuticle Branchial folds in the cloacal chamber Radula absent usually present from the Spic- Copulatory spines carinata verrilli, sp nov Body tliick-set, unkeeled, 25 mm ventral folds, 30-40 branchial folds Gulf of St Lawrence, 313 fathoms, in length (p 206) in several layers may be present shell gland, Free PRONEOMENIA Body Cuticle Gills usually lacking sometimes separated thick Copu- living, partly or entirely parasitic Hdbrecht, ISSO elongated, vermiform, the length 9-50 times the diameter opening ventral SaU- lacking Cuticle thick, spicules mostly needle- Epidermal papillae present Coelomoducts usually united into a latory spicules Simroth Radula distichous or polystichous, sometimes vary glands tubular, lobed or lacking like greatest thickness Accessory copulatory apparatus present PRONEOMENIIDAE Worm-like by mm Cloacal Foot present, the groove passing into the cloacal chamber with crowded spicules in several layers No gills Radula DONDERSIIDAE 192 Two multidentate Type P salivary Copulatory spines present or absent glands of genus, P sluiteri acuminata Wiren Length index Radula 9.3 present, DORYMENIA (p Hkath, 215) 1911 Vermiform, body terminating posteriorly in a finger-shaped elongation Radula multidentate with 9-51 longitudinal rows One transverse row from 9-22 teeth of A pair of seminal receptacles in each pair of long copulatory spicules closely associated with a pair of globular coeca or deep pits likewise opening separately into the cloacal chamber D peroneopsis, by mm in greatest thickness Radula with teeth and 22 teeth in each transverse row Accessory in length longitudinal rows of copulatory apparatus present fms Off the Massachusetts coast at a depth of 222) (p STROPHOMENIA Body ules Two and of genus, D acuta sp nov Body 25 mm 1,753 Type Pruvot, 1899 elongated, cyUndrical, the thick cuticle penetrated acicular spic- Radula and salivary ducts present genital openings into the cloacal chamber usually present Type closely distinct by crowded vesicular papillae of genus, S lacazei S agassizi, sp nov Worm-hke, 22-37 mm in length by stalked, numerous; spicules needle-Uke glands tubular G77 fms (p Nine 1.1-1.5 Radula average diameter Radula very pairs of seminal receptacles small Papillae Ventral salivary Off Massachusetts coast, 229) DONDERSIIDAE Body mm Simroth often worm-like; cuticle thin; spines flat and soUd distichous, monoserial or lacking tube-Uke Gill folds lacking apparatus may be present ing free upon corals, etc Papillae lacking SaUvary glands globular, sac- or Coelomoducts united or separate Copulatory Ventral fold and furrow may be absent Liv- PLATE 11 Fig "ALE^ffRoss" Atlantic Soixnogastres PUTF 11 \ m£jm A f' 7/ ^-sscriife^ I; ii ^v:" "^m ""'^^mm^":'"' «^«"-'V"'»„,.^ '^X(\^S\ \'S^*,JL^-'-i^ ^^'^fe ""