HARVARD UNIVERSITY LIBRARY OF THE Museum of Comparative Zoology [kos. c t.....a.,ir OCT la 1927 MEMOIRS OF THE MUSEUM (»F COMPARATIVE ZOOLOOY AT HARVARD COLLEGE. VOL. XLVIII. CAMBRIDGE, MASS., U. S. A. lPiiute& for tbe /HMiseum. 1919. MEMOIRS OF THE MUSEUM OF COMPARATIVE ZOOLOGY AT HARVARD COLLEGE. VOL. XLVIII. CAMBRIDGE, MASS., U. S. A. lPrinte& for tbe /IDuseum. 1919. O, The Cosmos Press: Cambridge, Mass., U. S. A. /iDemotrs of tbe /IDuseum of Comparattve Zoolog? AT HARVARD COLLEGE. Vol. XLVIII. REPORTS ON AN EXPLORATION OFF THE WEST COASTS OF MEXICO, CEN- TRAL AND SOUTH AMERICA, AND OFF THE GAL.iPAGOS ISL.ANDS, IN CHARGE OF ALEXANDER AGASSIZ, BY THE U. S. FISH COMMISSION STEA]\IER "ALBATROSS," DURING 1891, LIEUT.-COMISIANDER Z. L. TANNER, U. S. N., COMMANDING. XXXVIII. REPORTS ON THE SCIENTIFIC RESULTS OF THE EXPEDITION TO THE TROPICAL PACIFIC, IN CHARGE OF ALEX.\NDER AGASSIZ, BY THE U. S. FISH COMMISSION STEAMER "ALBATROSS," FROM AUGUST, 1899, TO MARCH, 1900, COMMANDER .JEFFERSON F. MOSER, U. S. N., COMMANDING. XX. REPORTS ON THE SCIENTIFIC RESULTS OF THE EXPEDITION TO THE EAST- ERN TROPICAL PACIFIC, IN CHARGE OF ALEXANDER AGASSIZ, BY THE U. S. FISH COMIMISSION STEAMER "ALBATROSS," FROM OCTOBER, 1904, TO MARCH, 1905, LIEUT.-COMMANDER L. M. GARRETT, U. S. N., COM- MANDING. XXXL THE ANNELIDA POLYCHAETA. By RALPH V. CHAMBERLIN. WITH EIGHTY PLATES. TEXT. [Published by permission of Hugh M. Smith, U. S. Cominissioner of Fish and Fisheries]. CAMBRIDGE, U. S. A.: prtnteC) for tbe /Cuseum. JCLY, 1919. CONTENTS. REPORTS on an Exploration off the West Coasts of Mexico, Central and South America, and off the Galapagos Islands, in charge of Alexander Agassiz, by the U. S. Fish Commission Steamer "Albatross," during 1891, Lieut. Commander Z. L. Tanner, U. S. N., Commanding. XXXVIII. Reports on the Scientific Results of the Expedi- tion to the Tropical Pacific, in charge of Alexander Agassiz, by the U. S. Fish Com- mission Steamer "Albatross," from August, 1899, to March, 1900, Commander Jeffer- son F. MosER, U. S. N., Commanding. XX. Reports on the Scientific Results of the Expedition to the Eastern Tropical Pacific, in charge of Alex.\nder Agassiz, by the U. S. Fish Commission Steamer " Albatross," from October, 1904, to March, 1903, Lieut.-Commander L. M. Garrett, U. S. N., Commanding. XXXI. The Annelida Polych.\eta. By Ralph V. Chamberlin. 514 pp. 80 plates. July, 1919. TABLE OF CONTENTS. Page Introduction 13 Lists of Species 14 Expedition of 1890-1891 ... 14 Expedition of 1899-1900 ... 14 Expedition of 1904-1905 ... 15 Atlantic Expeditions, 1884-1887 . 16 Bathymetrical Distribution .... 16 Littoral Zone, 0-50 fms. ... 16 Continental Zone, 50-500 fms. . 16 Abyssal Zone, below 500 fms. . 16 Pelagic Zone IS Classification 18 Key to the Families 19 Amphinomidae 23 Key to Genera 25 Synonymy of Genera 25 Notopygos Grube 25 N. maculata (Kinberg) 26 Hermodice Kinberg 26 H. striata Kinberg 26 Amphinome Bruguiere 26 A. vagans (Savigny) 27 Eurj'thoe Kinberg 27 E. complanata (Pallas) 28 Chloeia Savigny 30 C. entypa, sp. nov 31 Euphrosynidae 32 Key to Genera 32 Euphrosyne Savigny 32 E. panamica, sp. nov 33 Polynoidae 35 Key to Genera 37 Synonymy of Genera 40 Plotolepis, gen nov 40 P. nans, sp. nov 41 Podarmus, gen. nov 45 P. ploa, sp. nov 46 Harmopsides, gen. nov 48 natans, sp. nov 48 Harmothoe Kinberg 51 Page H. hirsuta Johnson 51 H. mexicana, sp. nov. 54 Eunoe Malmgren . . . 58 E. eura, sp. nov. . . . 58 Lepidasthenia Malmgren 61 Key to Species . . 61 L. curta, sp. nov. 61 Iphione Kinberg . 64 L ovata Kinberg . 64 Admetella Mcintosh 64 A. hastigerens, sp. nov. 64 A. dolichopus, sp. nov. . 67 Polynoe Savigny . . . 70 P. innatans, sp. nov. 70 P. nesiotes, sp. nov. . . 72 Lepidonotus Leach 74 L. johnstoni Kinberg 74 L. nesophilus, sp. nov. . 75 Aphroditidae 78 Key to Genera . . . 79 Aphrodita Linne . . . 79 A. defendens, sp. nov. . 80 Laetmonice Kinberg 81 L. wyvillei Mcintosh 82 L. benthaliana Mcintosh 82 L. sp 83 Pontogenia Claparede . 83 P. curva, sp. nov. . . 83 Acoetidae 85 Key to Genera . . . 85 Synonymy of Genera 86 Panthalis Kinberg . . 86 P. panamensis, sp. nov. 86 Sigalionidae 89 Key to Genera . . . 89 Synonymy of Genera 90 Sthenolepis Willey . . 90 S. areolata (Mcintosh) . 90 Sigalion Cuvier . . . . 91 S. pourtalesi Ehlers . . . 91 8 CONTENTS. Page Polylepididae 91 Key to Genera 91 Synonymy of Genera 91 Palmyridae 92 Key to Genera 92 Chrysopetalidae 92 Key to Genera ....... 92 Nepthydidae 92 Nepthys Cuvier 93 N. ectopa, sp. nov 94 N. sp 97 Phyllodocidae 97 Key to the Snbt'amilies and Genera . 99 Synonymy of Genera 101 Anaitides Czerniawsky 102 Key to Species 102 A. lamellifera (Pallas) 10.3 A. patagonica (Kinberg) . . .' . 104 A. compsa, sp. nov 10.5 Phj-llodoce Savigny 108 P. fakaravana, sp. nov 108 P. medipapillata Moore . . . . Ill P. sp. a HI P. sp. b 112 P. sp. c 113 Lopadorrhynchus Grube . . . . 113 Key to Species 1 14 L. parvum, sp. nov 114 L. nans, sp. nov 116 Mastigethus, gen. nov 119 M. errans, sp. nov 120 Pelagobia Greeff 122 Key to Species 122 P. viguieri Gravier 122 Nans, gen. nov 125 N. simplex, sp. nov 125 Pontodoridae 127 lospilidae 127 Key to Genera 128 Lacydoniidae 128 Otopsidae . 128 Pisionidae 128 Key to Genera 128 Alciopidae 129 Key to Genera 130 Alciopa Audouin & Milne Edwards . 130 A. cantrainii (Delle Chiaji) . . . 130 Torea Quatrefages 131 T. pelagica, sp. nov 131 Page Vanadis Claparede . 133 Key to Species 133 V. formosa Claparede .... . 134 Mauita, gen. nov 135 M. nans, sp. nov 136 Halodora Greeff . 139 H. reynaudii (Audouin & Miln( Edwards) . 139 Corynocephalus Levinsen . . . . 141 Key to Species 141 C. paumotanus, sp. nov. . . . 141 Plotohelmis, gen. nov 143 P. alata, sp. nov. 144 Rhynchonerella A. Costa . . . 146 Key to Species 146 R. cincinnata (Greeff) .... . 146 R. pycnocera, .sp. nov 147 R. parva, sp. nov 150 Typhloscolecidae 151 Key to Genera 152 Typhloscolex Busch 152 T. miillerii Busch 152 Sagitella N. Wagner .... 153 S. kowalewskii N. Wagner . . . 153 S. sp. a 153 Plotobia, gen. nov 1.54 P. simplex, sp. nov 1.55 P. coniceps, sp. nov 156 Tomopteridae 1.58 Tomopteris Eschscholtz . . . 159 T. innatans, sp. nov 1.59 T. eura, sp. nov 160 T. idiura, sp. nov 161 T. sp. a 162 T. sp. b 162 Svllidae 163 Kev to the Subfamilies and Genera 164 Synonymy of Genera .... 166 Autolytus Grube 167 A. obliquatus, sp. nov 168 A. planipalpus, sp. nov. . . . 170 A. torquens, sp. nov 172 Syllis Savigny 174 Key to Subgenera 174 S. remex, sp. nov 175 Synelmis, gen. nov 176 S. simplex, sp. nov. ..... 177 Odontosyllis Claparede .... 180 0. atypica, sp. nov. ..... 180 CONTENTS. 9 Page Sphaerodoridae 182 Key to Genera 182 Synonymy of Genera 182 Hesionidae 183 Key to Genera 185 Synonymy of Genera 185 Hesione Savigny 186 H. paeifica Mcintosh 186 H. genetta Grube 186 H. panamena, sp. nov 188 Leocrates Kinberg 190 L. iris (Grube) 190 L. anomalus, sp. nov 190 Nereidae 191 Key to Genera 194 Synonymy of Genera 195 Kainonereis, gen. nov 196 K. alata, sp. nov 197 Nereis Linne 202 N. segrex, sp. nov 202 N. leuca, .sp. nov 205 N. caenoeirrus, sp. nov 209 N. pelagica Linne 213 Ceratonereis Kinberg 213 C. fakaravae, sp. nov 213 Uneinereis, gen. nov 215 U. subita, sp. nov 216 Platynereis Kinberg 219 P. polyscabna, sp. nov 219 Perinereis Kinberg 227 P. helleri Grube 227 Pseudonereis Kinberg 227 P. atopodon, sp. nov 228 Leodicidae 229 Key to Genera 231 Synonymy of Genera 232 Leodice Savigny 232 Key 232 L. makemoana, sp. nov 233 L. siciliensis (Grube) 236 L. segregata, sp. nov 237 L. lita, sp. nov 240 L. oliga, sp. nov 244 L. oliga papeetensis, subsp. nov. . . 248 L. pauroneurata, sp. nov 249 L. nesiotes, sp. nov ' . 253 Key 256 L. panamena, sp. nov 256 L. contingens, sp. nov 260 Onuphididae Key to Genera . . . Onuphis Audouin & Milne Key O. proalopus, sp. nov O. nannognathus, sp. nov. O. litabranchia, sp. nov O. paciiytmema, sp. nov O. socia, sp. nov. . O. iepta, sp. nov. Key O. crassisetosa, sp. nov. O. cobra, sp. nov. Paronuphis Ehlers P. solenotecton, sp. nov. Hyalinoecia Malmgren H. tecton, sp. nov. H. tubicola (O. F. Muiler) H. leucacra, sp. nov. Leptoecia, gen. nov. L. abyssorum, sp. nov. Lumbrinereidae . . . Key to Genera S\nonymy of Genera Lumbrinereis Blainville L. bifilaris Ehlers Cenothri.x, gen. nov. C. mutans, sp. nov. . Cenogenus, gen. nov. C. descendens, sp. nov. Oenone Savigny . . O. telura, sp. nov. Dorvilleidae .... Key to Genera . . Synonymy of Genera Dorvillea, Parfitt D. crassa, sp. nov. Glyceridae .... Key to Genera . . Synonymy of Genera Tehike, gen. nov. T. epipolasis, sp. nov. Hemipodus Quatrefages H. mexicanus, sp. nov. Glycera Sa\igny . G. dibranchiata Ehlers G. profundi, sp. nov. G. fundicola, sp. nov. Edwards Paqb . 263 . 264 . 265 . 265 . 265 . 270 . 274 279 284 290 295 295 300 306 306 310 310 315 317 319 320 324 325 326 327 327 329 330 333 333 334 334 338 339 339 339 339 343 344 344 345 346 348 349 350 350 3.50 352 10 CONTENTS. Page Ariciidae 353 Key to Genera 354 Niiinereis Blainville 354 N. retusiceps, sp. nov 355 Branchethus, gen. nov 357 B. latum, sp. nov 358 Paraonidae 361 Key to Genera 362 Goniadidae 362 Key to Genera 363 Synonymy of Genera 363 Goniada Audoiiin & Milne Edwards . 363 G. eremita Audouin & Milne Ed- wards 363 Chaetopteridae 363 Key to Genera 365 Synonymy of Genera 365 C'haetopterus Cuvier 366 C. pergamentaceus Cuvier . . . 366 Spionidae 367 Key to Genera 368 Synonymy of Genera 369 Boccardia Ha.swell 369 B. polybranchia (Haswell) . . . 369 Disomididae 369 Key to Genera 369 Sj'nonymy of Genera 370 Cirratulidae 370 Key to Genera 372 Cirrineris Blainville 372 C. nesiotes, sp. nov 373 Cirratulus Lamarck 374 C. megalus, sp. nov. 375 C. sinincolens, sp. nov. .... 377 C. danielseni Hensen 379 Audouinia Quatrefages 380 A. filigera nesophila, subsp. nov. . 380 Dodecaceria Oersted 381 D. concharum Oersted 381 Opheliidae 382 Key to Genera 384 Synonymy of Genera 385 Kesun, gen. nov 385 K. fusus, sp. nov 386 Travisia Johnston 387 T. profundi, sp. nov 387 Scalibregmidae 389 Key to Genera 390 Synonymy of Genera 390 Scalibregma H. Rathke S. inflatum H. Rathke Arenicolidae .... Key to Genera Arenicola Lamarck A. cristata Stimpson Flabelligeridae . . . Key to Genera Synonymy of Genera Flabelligera M. Sars F. infundibularis Johnson F. affinis M. Sars Brada Stimpson B. verrucosa, sp. nov. B. irenaia, sp. nov. Ilyphagus, gen. nov. L hythincola, sp. nov 1. pluto, sp. nov. . I. ascendens, sp. nov. Sternaspidae . . . Sternaspis Otto S. fossor Stimpson S. maior, sp. nov. Maldanidae Key to the Subfamilies and Synonymy of Genera Petaloproctus Quatrefages P. crenatus, sp. nov. Maldanella Mcintosh M. fibrillata, sp. nov. Sonatsa, gen. nov. S. meridionalis, sp. nov. Gen. et .sp. ? . . . Ammocharidae Terebellidae .... Key to the Subfamilies Synonymy of Genera Terebella Linne T. panamena, sp. nov. Nicolea Malmgren N. taboguillae, sp. nov. N. galapagensis, sp. nov N. profundi, sp. nov. N. latens, sp. nov. Eupolymnia Verrill . E. regnans, sp. nov. . E. insulana, sp. nov. Thelepus Leuckart T. pericensis, sp. nov. and Genera Genera Page 391 392 392 394 394 394 394 396 397 397 397 397 399 399 400 402 402 403 403 404 405 405 , 406 407 409 . 410 . 410 . 410 , 412 . 413 . 415 . 416 . 418 . 418 . 418 420 . 423 . 424 . 424 . 425 . 425 . 427 . 429 . 430 . 432 . 433 . 434 . 437 . 437 CONTENTS. 11 Terebellides M. Sars T. eurystethus, sp. nov. Ampharetidae . . . Key to the Subfamilies SynonjTTiy of Genera Ampharete Malmgren A. hoina, sp. nov. Amphicteis Grube A. obscurior, sp. nov. A. uncopalea, sp. nov. A. orphnius, sp. nov. Moyanus, gen. nov. . M. explorans, sp. nov. Sabellides Milne Edwards S. dolus, sp. nov. Pablts, gen. nov. . P. deroderus, sp. nov. Paiwa, gen. nov. P. abyssi, sp. nov. Gen. et sp Amphictenidae . . . Key to Genera Cistenides Malmgren C. granulata (Linne) Capitellidae .... Key to Genera . . Page 438 438 440 442 444 444 444 447 447 448 450 451 452 455 455 450 457 459 459 461 461 463 463 463 463 465 Synonymy of Genera Notomastus Sars . . . N. latericeus Sars Sabellidae Key to Genera . . SjTionymy of Genera Dasychonopsis Bush D. nigromaculata (Baird) Serpulidae Key to Genera . . . Synonymy of Genera Pomatoceros Philippi P. paumotanus, sp. nov. Spirobranchus Blainville S. tricornis (Morch) . Paumotella, gen. nov. P. takemoana, sp. nov Sabellariidae .... Key to Genera Synonymy of Genera Idanthyrsus Kinberg I. cretus, sp. nov. I. regalis, sp. nov. Tetreres CauUery T. nesiotes, sp. nov. Index Page 466 406 40() 460 408 470 472 472 472 473 477 479 479 481 481 481 482 483 484 484 485 485 487 490 490 495 ALBATROSS POLYCHAETA. INTRODUCTION. The annelids with which the present memoir is concerned are embraced in collections made by the Albatross dming three distinct expeditions in charge of Mr. Alexander Agassiz to contiguous, and in some degree overlapping, areas of the Tropical Pacific Ocean. In the first of these, explorations were made off the west coasts of Mexico, Central, and northern South America, and off the Galapagos Islands from February to May, 1891. So far as con- cerns the polychaetes collected, the second expedition covered the region from the Marquesas and Paumotus westward to the EUice, Gilbert, and Marshall Islands and was carried on from September, 1899, to March, 1900. The third expedition, continued from October, 1904, to March, 1905, covered an extensive area principally off the South American coast from Panama southward to Peru and eastward to the Galapagos, Easter Island, and the Paimiotus. In addition, thirteen species from earUer expeditions of the Albatross in the Atlantic are hsted in this Memoir. These three expeditions, with the exception in some degree of the second, covered areas essentially untouched by other expeditions, and the annelid forms have proved in large measure new. No fewer than one hundred and eighteen out of a total of one hundred and seventy-five species seem not to have been previously described, these including twenty-three new generic types of which several are of high interest. Wliile the Uttoral forms are well represented, these coming chiefly from Panama and the Polynesian Islands, chief interest attaches to the abyssal and pelagic species. The collection of pelagic species is exceptionally rich and important. Aside from relatively numerous representatives of strictly pelagic families, such as the Alciopidae, Typhloscolecidae, and Tomopteridae, many forms from other famiUes were seciued which are either in the epitokous pelagic phase or are completely pela- gic. Mention may be made of the epitokes of the Nereidae, including the 14 THE ANNELIDA POLYCHAETA. peculiar new genus Kainonereis taken by night light off the Gilbert Islands, and those of the Syllidae, including the new generic type Synelmis. Consider- able additions are made to the pelagic species of the Phyllodocidae, two repre- senting new genera, Mastigethus and Nans. To the six previously known pelagic Polynoidae, four are added, three being types of genera of which atten- tion may be called to Plotolepis, a form showing peculiar adaptations to life at the surface in its greatly elongate and inflated notocirri and in its vesicular though reduced elytra. Complete lists of the forms taken in the different bathymetrical zones are given (p. 16-18). Separate lists of the forms secured by the different expeditions are here given. It may be noted that dupUcation of species is negUgible. LISTS OF SPECIES. Chloeia entypa, sp. nov. Harmothoe mexicana, sp. nov. Lepidasthenia curta, sp. nov. Admetella doHcliopus, sp. nov. Polynoe nesiotes, sp. nov. Laetmonice benthaliana Mcintosh sp. Nepthys sp. Anaitides compsa, sp. nov. Phyllodoce medipapillata Moore Hesione panamena, sp. nov. Leodice segregata, sp. nov. pauroneurata, sp. nov. panamena, sp. nov. Onuphis nannognathus, sp. nov. litabranchia, sp. nov. lepta, sp. nov. crassisetosa, sp. nov. cobra, sp. nov. Paronuphis solenotecton, sp. nov. Hyalinoecia tecton, sp. nov. tubicola (O. F. Miiller) leucacra, sp. nov. Expedition of 1891. Lumbrinereis bifilaris Ehlers Hemipodus mexieanus, sp. nov. Glycera profundi, sp. nov. Branchethus latum, gen. et sp. nov. Chaetopterus pergamentaceus Cuvier Cirratulus sinincolens, sp. nov^ Brada verrucosa, sp. nov. irenaia, sp. nov. Ilyphagus bythincola, sp. nov. Sternaspis fossor Stimpson maior, sp. nov. Maldanella fibrillata, sp. nov. Maldanidarum, gen. et sp.? Nicolea latens, sp. nov. Eupolymnia regnans, sp. nov. Thelepus pericensis, sp. nov. Ampharete lioma, sp. nov. Ampharetiilarum, gen. et sp.? Amphicteis obscurior, sp. no\'. uneopalea, sp. nov. orphnius, .sp. nov. Sabellides delus, sp nov. Spirobranchus tricornis (Morch) Hermodice striata Kinberg Amphinome V9,gans (Savigny) Eurythoe coniplanata (Pallas) Iphionc ovata Kinberg Panthalis panamensis, sp. nov Expedition of 1899-1900. Phylloiloce t'akaravana, sp. nov. sp. Nans simplex, gen. et sp. nov. Ilalodora reynaudii (Audouin and Milne Edwards) LISTS OF SPECIES. 15 Corynocephalus paiimotamis, sp. nov. Plotohelmis alata, sp. nov. Rhynchonerella par\a, sp no\-. Typhloscolex miilleri Busch Tomopteris innatans, sp. nov. Autolytus obliquatus, sp. nov. planipalpus, sp. nov. torquens, sp. nov. Syllis remex, sp. nov. Synelmis simplex, gen. et sp. nov. Odontosj'Uis atypica, sp. nov. Hesione pacifica Mclntosli genetta Grube Leocrates iris (Grube) anomalus, sp. nov. Kainonereis alata, gen. et sp. nov. Nereis leuca, sp. nov. caenocirnis, sp. nov. Ceratonereis fakaravae, sp. nov. Platynereis polyscalma, sp. nov. Perinereis helleri Grube Pseudonereis atopodon, sp. nov. Leodice makemoana, sp. nov. lita, sp. nov. oliga, sp. nov. oliga papeetensis, subsp. nov. nesiotes, sp. nov. Oenone telura, sp. nov. Dorvillea crassa, sp. nov. Telake epipolasis, gen. et sp. nov. Nainereis retusiceps, sp. nov. Kesun fusus, gen. et sp. nov. Pabits deroderus, gen. et sp. nov. Pomatoceros paumotanus, sp. nov. Paumotella takemoana, gen. et sp. nov. Tetreres nesiotes, sp. nov. Expedition of 1904-1905. Notopygos maeulata (Kinberg) Amphinome vagans (Savigny) Eurytlioe eomplanata (Pallas) Euphrosyne panamica, sp. nov. Plotolepis nans, gen. et sp. nov. Podarmus ploa, gen. et sp. nov. Harmopsides natans, gen. et sp. nov. Harmothoe hirsuta Johnson Eunoe eura, sp. nov. Admetella hastigerens, sp. nov. Polynoe innatans, sp. nov. Lepidonotus johnstoni Kinberg nesophilus, sp. nov. Aphrodita defendens, sp. nov. Laetmonice w\'villei Mcintosh benthaliana Mcintosh Sthenolepis areolata (Mcintosh) Nephtys ectopa, sp. nov. Anaitides lamellifera (Pallas) patagonica (Kinberg) Phyllodoce sp. b. sp. c. Lopadorrhynehus parvum, sp. nov. nans, sp. nov. Mastigethus errans, gen. et sp. nov. Pelagobia viguieri Gravier Alciopa cantrainii (Delle Chiaji) Torea pelagica, sp. nov. Vanadis formosa Claparede ]\Iauita nans, gen. et sp. nov. Halodora reynaudii (Audouin and Milne Edwards) Corynocephalus paumotanus, sp. nov. Rhynchonerella cincinnata (Greeff) pycnocera, sp. nov. Sagitella kowalewskii N. Wagner sp. a. Plotobia simplex, gen. et sp. nov. coniceps, sp. nov. Tomopteris innatans, sp. nov. eura, sp. nov. idiura, sp. nov. sp. a. sp. b. Nereis segrex, sp. nov. Uncinereis subita, gen. et sp. nov. Perinereis helleri Grube. Leodice siciliensis (Grube) contingens, .sp. nov. Onuphis proalopus, sp. nov. pachytmema, sp. nov. socia, sp. nov. crassisetosa, sp. nov. Hyalinoecia tubicola (O. F. Miiller) Leptoecia abyssorum, gen. et sp. nov. Lumbrinereis bifilaris Ehlers. 16 THE ANNELIDA POLYCHAETA. Cenothrix mutans, gen. et sp. nov. Cenogenus descendens, gen. et sp. nov. Glycera fumlicola, sp. nov. Cirrineris nesiotes, sp. nov. Cirratulus megalus, sp. nov. Audouinia filigera nesophilus, subsp. nov. Travisia profundi, sp. nov. Ilyphagus pluto, gen. et sp. nov. ascendens, gen. et sp. nov. Petaloproctus crenatus, sp. nov. Sonatsa meridionalis, gen. et sp. nov. Terebella panamena, sp. nov. Nicolea taboguillae, sp. nov. galapagensis, sp. nov. profundi, sp. nov. latens, sp. nov. Eupolymnia insulana, sp. nov. Terebellides eurystethus, sp. nov. Moyanus explorans, gen. et sp. nov. Paiwa abyssi, gen. et sp. nov. Idanthyrsus cretus, sp. nov. regalis, sp. nov. Atlantic Expeditions 1884-1890. Pontogenia curva, sp. nov. Sigalion pourtalesi Ehlers Nereis pelagica Linne Glycera dibranchiata Ehlers Goniada eremita Audouin & Milne Edwards Cirratulus danielseni Hansen Dodecaceria concharum Oersted Scalibregma inflatum H. Rathke Arenicola cristata Stinipson Flabelligera affinis M. Sars Cistenides granulata (Linne) Notoniastus latericeus Sars Dasychonopsis nigromaculata (Baird) Bathymetrical Distribution. The bathymetrical distribution of the species may be incUcated sufficiently by means of the following Usts. Littoral Zone {0 to 50 fms.). Notopygos maculata (Kinberg) Hermodice striata Kinberg Eurythoe complanata (Pallas) Euphrosyne panamiea, sp. nov. Harmothoe hirsuta Johnson Iphione ovata Kinberg Polynoe nesiotes, sp. nov. Lepidonotus johnstoni Kinberg nesophilu.s, sp. nov. Pontogenia curva, sp. nov. Panthalis panamensis, sp. nov. Sigalion pourtalesi Ehlers Nepthys sp. Anaitides lamellifera (Pallas) compsa, sp. nov. Phyllodoce fakaravana, sp. nov. medipapillata Moore sp. a. Synelmis simplex, gen. et. sp. nov. Hesione pacifica Mcintosh genetta Grube panamena, sp. nov. Leocrates iris (Grube) anomalus, sp. nov. Ceratonereis fakaravae, sp. nov. Perinereis helleri Grube Pscudonereis atopodon, sp. nov. Leodice makemoana, sp. nov. siciliensis, (Grube) lita, sp. nov. oliga, sp. nov. oliga papeetensis, subsp. nov. nesiotes, sp. nov. panamena, sp. nov. Cenothrbc mutans, gen. et sp. nov. Oenone telura, sp. nov. LISTS OF SPECIES. 17 Dorvillea crassa, sp. nov. Nainereis retusiceps, sp. nov. Chaetoptenis pergamentaceus Cuvier Cirrineris nesiotes, sp. nov. Audouinia filigera nesophilus, subsp. nov. Dodecaceria concharum Oersted Flabelligera affinis M. Sars Terebella panamena, sp. nov. Nicolea taboguillae, sp. nov. galapagensis, sp. nov. EnpoI\Tnnia regnans, sp. nov. Thelepus pericensis, sp. nov. Dasychonopsis nigromaculata (Baird ) Pomatoceros paumotanus, sp. nov. Spirobranchus tricornis (]M6rch) Paumotella takemoana, gen. et sp. nov. Idanthyrsus cretiis, sp. nov. regalis, sp. nov. Tetreres nesiotes, sp. nov. Continental Zone (50 to 500 fms.). Chloeia entypa, sp. nov. Laetmonice benthaliana Mcintosh Sthenolepis areolata (jMcIntosh) Leodice segregata, sp. nov. pauroneurata, sp. nov. eontingens, sp. nov. Onuphis crassisetosa, sp. nov. Glycera dibranchiata Ehlers Branchethiis latum, gen. et sp. nov. Goniada eremita Audouin and Milne Edwards Scalibregma inflatum H. Rathke Flabelligera infundibularis Johnson Brada verrucosa, sp. nov. Sternaspis fossor Stimpson Eupoljinnia insulana, sp. nov. Amphicteis obscurior, sp. nov. orphnius, sp. nov. Cistenides granulata (Linne) Notomastus latericeus Sars Abyssal Zone (beloiv 500 fms.). a. 500 to 1,000 f?ns. Harmothoe mexicana, sp. nov. Lepidasthenia curta, sp. nov. Admetella hastigerens, sp. nov. dolichopus, sp. nov. Laetmonice benthaliana Mcintosh Anaitides patagonica (Kinberg) Nereis segrex, sp. nov. Uncinereis subitus, gen. et sp. nov. Leodice segregata, sp. nov. Onuphis proalopus, sp. nov. nannognathus, sp. nov. crassisetosa, sp. nov. Hyalinoecia tecton, sp. nov. tubicola (O. F. Miiller) leucacra, sp. nov. Limibrinereis bifilaris Ehlers Hemipodus mexicanus, sp. nov. Glycera profundi, sp. nov. Cirratulus megalus, sp. nov. sinincolens, sp. nov. Ilj^phagus ascendens, gen. et sp. nov. Sternaspis maior, sp. nov. Petaloproctus crenatus, sp. nov. Nicolea latens, sp. nov. Terebellides eurystethus, sp. nov. Ampharete homa, sp. nov. Ampharetidarum, gen. et sp.? Amphicteis uncopalea, sp. nov. Sabellides delus, sp. nov. Aphrodita defendens, sp. nov. Laetmonice sp. Nepthys ectopa, sp. nov. Onuphis litabranchia, sp. nov. h. 1000 to 2000 fms. Onuphis lepta, sp. nov. cobra, sp. nov. Paronuphis solenotecton, sp. nov. Hyalinoecia tubicola (O. F. Miiller) 18 THE ANNELIDA POLYCHAETA. Brada irenaia, sp. nov. Ilyphagus bythincola, gen. et sp. nov. Maldanella fibrillata, sp. nov. Maldanidanim, gen. et sp.? Nicolea profundi, sp. nov. c. 2000 fms. and below. Eiinoe eura, sp. nov. Laetmonice wy\'illei Mcintosh Onuphis pachytmema, sp. nov. socia, sp. nov. Leptoecia abyssorum, gen. et sp. nov. Cenogenus descendens, gen. et sp. nov. Kesun fusus, gen. et sp. nov. Travisia profundi, sp. nov. Ilyphagus phito, gen. et sp. nov. Sonatsa meridionahs, gen. et sp. nov. TerebelHdes eurystethus, sp. nov. Moyanus explorans, gen. et sp. nov. Pabits deroderus, gen. et sp. nov. Paiwa abyssi, gen. et sp. nov. Pelagic Zone. Amphinome vagans (SavignjO (on drift) Plotolepis nans, gen. et sp. nov. Podarmus ploa, gen. et sp. nov. Harmopsides natans, gen. et sp. nov. Polynoe innatans, sp. nov. Phyllodoce sp. c. Lopadorrhynchus parvum, sp. nov. nans, sp. nov. Mastigethus errans, gen. et sp. nov. Pelagobia viguieri Gravier Nans simplex, gen. et sp. nov. Alciopa cantrainii (Delle Chiaji) Torea pelagica, sp. nov. Vanadis formosa Claparede. Mauita nans, gen. et sp. nov. Halodora reynaudii (Audouin and Milne Edwards) Corynocephalus paumotanus, sp. nov. Plotohelmis alata, gen. et sp. nov. Rhynchonerella cincinnata (Greeff) pycnocera, sp. nov. parva, sp. nov. Typhloscolex miilleri Busch Sagitella kowalewskii N. Wagner sp. a. Plotobia simplex, gen. et sp. nov. coniceps, gen. et sp. nov. Tomopteris innatans, sp. nov. eura, sp. nov. idiura, sp. nov. sp. a. sp. b. Autolytus obliquatus, sp. nov. planipalpus, sp. nov. torquens, sp. nov. Syllis remex, sp. nov. Odontosyllis atypica, sp. nov. Kainonereis alata, gen. et sp. nov. Nereis leucua, sp. nov. caenocirrus, sp. nov. Platynereis polyscalma, sp. nov. Telake epipolasis, gen. et sp. nov. Glycera fundieola, sp. nov. CLASSIFICATION. The various efforts to divide the Polychaeta as a whole into major groups have not proved satisfactory and many difficulties remain to be sur- mounted before the broader affinities of the famiUes can be elucidated. It seems best at present to follow the method used by Malmgren and various recent writers in considering the families separately and arranging them in an order bringing the more obviously related groups into general proximity. While CLASSIFICATION. 19 the families in the main are compact and unquestionably natural assemblages, in certain cases families as received by some are by others divided into two or more less comprehensive ones. I have here, in general, favored the narrower limitation of the famiUes; but it seems very convenient and desirable to have names for designating a number of the obviously natural assemblages of such famihes even though the majority of the famihes are left outside any such grouping. I have accordingly introduced a number of superfamily names. Thus, the elytra-bearing famiUes Polylepididae, Sigahonidae, Acoetidae, Polynoidae, and Aphroditidae (i.e., the Aphroditidae sens. lat. of some authors) are placed in a superfamily Aphroditoidea; the Leodicidae, Onuphi- didae, Lumbrinereidae, and DorvUleidae {noni. nov. pro StaurocephaUdae or Stauronereidae) in the Leodicoidea; the Glyceridae and Goniadidae in the Glyceroidea; the DisomicUdae {nom. nov. -pro Disomidae), Spionidae and Apis- thobranchidae in the Spionoidea ; the Spintheridae, Euphi'osynidae, and Amphino- midae in the Amphinomoidea; the Alciopidae, Lacydoniidae, lospilidae, Ponto- doridae, and Phyllodocidae in the Phyllodocoidea; the Syllidae and Hesionidae m the Sylloidea; the Serpuhdae and Sabellidae in the Serpuloidae; and the Terebelhdae, Ampharetidae, and Amphictenidae in the Terebelloidea. Key to the Families. a. Prostomium freely exposed. 6. Body bearing true elytra Aphroditoidea. c. Elytra borne on all somites; neurocirri and dorsal branchiae rudimentary. . . .Polylepididae. cc. Elytra not on all somites. d. Elytra alternating with cirri in the anterior region but in the posterior region occurring on all somites, these at the same time bearing cirri or cirrlform branchiae Sigalionidae. dd. Elytra not thus arranged. e. Elj'tra and cirri alternating almost regularly somite by somite. Two pedunculate eyes accompanied or not by sessile eyes; no facial tubercle; tentacles two or three; bodj' elongate • Acoetidae. ee. Elj-tra not thus regularly alternating with cirri, but occvu'ring on somites II, IV, and V,— or rarely on II, III, IV, and ^T, — and on alternate succeeding somites to posterior region and then on alternate groups of two or most posteriorly of tliree somites. /. Pharynx armed with four horny jaws; two or three tentacles; no facial tubercle, or this but weakly indicated Polynoidae. ff. Jaws none or rudimentary; a median tentacle alone present; facial tubercle well de- veloped Aphroditidae. 66. Body not bearing true elytra. c. Prostomium fused with the two succeeding somites and forming a head bifurcate in front and bearing four tentacular cirri of which the posterior pair are much the longer; other somites laterally prolonged and bearing biramous parapodia which are achaetous. . . . Tomopteridae. cc. Not so. d. Anterior somites (excepting rarely the first one to four) with neuropodial processes or tori nearlj' always more or less elongate at right angles to the axis of the body and linear, oval or lamellar in form, which bear numerous crochets or uncini in unmixed groups or series, or rarely the crochets few in number. 20 THE ANNELIDA POLYCHAETA. e. Body anteriorly either wholly without a group of filiform or branched branchial appendages, or these if present arising from the frayed margin of a campanuliform membrane sur- rounding the mouth except ventrally. /. With branched or arborescent branchiae on middle region of the body. . . . ArenicoUdae. ff. With no branchiae on middle region of body. g. No capillary setae, both notopodia and neuropodia bearing exclusively crochets, crochets few, with tori not elongate; body long, somites numerous; prostomium without appendages Uncinaselidae. gq. Capillary setae present. Tori much elongated with crochets numerous. h. The first three fascicles of notopodial setae without corresponding ventral setae; uncinigerous tori elongate and very narrow, almost line-like; branchiae often present as the frayed margin of a circumoral membrane Ammocharidae. hh. Either some other number than first three pairs of fascicles of notopodial setae or none at all without corresponding ventral setae; uncinigerous tori not hne-like, usually elliptic or oblong; never with a group of branchiae about the mouth. Maldanidae. ee. Body anteriorly with a group of filiform, dendritic or plumose branchiae. . . . Terebelloidea. f. With two pairs of tentacular cirri ; the most posterior division of the body consisting of five or six somites abruptly offset from the rest of the body, this caudal region short, flat and commonly ending in a short, thread-like process or cirrus Amphidenidae. ff. With no tentacular cirri; most posterior division of body not of this form, consisting of more than ten somites. g. Prostomium more or less fused with the peristomium and forming a supraoral lobe which bears numerous filiform tentacles, often in two groups, which are not at all retractile within the oesophagus; branchiae never more than three pairs, these commonly branched, or if simple nearly always of uniform thickness, filiform, only rarely subulate; anterior region never bearing series of stout paleae. . Terebellidae. gg. Prostomium distinct; tentacles retractile within the oesophagus; branchiae most commonly four pairs, rarely only three or two pairs, always simple and strongly pointed or subulate; third somite often bearing two rows of conspicuous paleae. Ampharetidae. dd. Crochets either lacking entirely on the first nine or more somites or, if present, never in unmixed groups or series but mingled with capillary setae. e. Buccal armature complex, including several to many pairs of maxillae Leodicoidea. f. No ventral cirri present; dorsal cirri rudimentary or foUaceou-s Lumbrinereidae. ff. Dorsal and ventral cirri present. g. Maxillae consisting of a few pieces only, these forming short series. h. A pair of frontal tentacles, and a total of seven; peristomium entire. . Onuphididae. hh. No frontal tentacles, the total from one to five; peristomium biannulate. Leodicidae. gg. Maxillae numerous, small, forming two long series Dorvilleidae. ee. Buccal armature simple or none. /. Capillary setae present only on the first nine to fourteen somites; elsewhere only crochets in series at the ends of which are the branchiae when present; tentacles two, small and retractile; parapodia in anterior region rudimentary, in the posterior none. Capitellidae. ff. Setae not thus arranged. • g. Body on each side above the parapodia with a series of nearly globular capsules (cirri) each of wliich contains a tube wound in a ball; parapodia uniramous and without acicula Sphaerodoridae. gg. Without such capsular cirri and non-aciculiferous parapodia. h. Prostomium long, conical and strongly annulated; bearing four short tentacles at its tip Glyceroidea. i. Parapodia of one form throughout the length of the body; proboscis with four similar jaws Glyceridae. a. Anterior parapodia uniramous, the others biramous; proboscis with numerous pieces in its armature Goniadidae. hh. Prostomium not thus annulated and with four tentacles at its tip. i. Prostomimn without true tentacles; palpi absent or else present in the form of two greatly elongated tentaculiform bodies. CLASSIFICATION. 21 j. Body posteriorly with a conspicuous paired sternal plate, from the edges of which radiate numerous fascicles of long slender setae Slemaspidae. jj. Body without this structure. k. Palpi present, greatly elongate and tentaculiform Spionoidea. I. First parapodia greatly developed, directed forwards and bearing long setae which meet in the middle in front of the head; short spines or crochets present on somites II and III and sometimes IV. .Disomididae. II. First parapodia not thus directed forward and bearing setae that cross in front; no stout spines on somites II, III, or IV. in. Parapodia distinctly biramous, with notopodial setae freely protrud- ing; a lamina caudad of each setigerous ramus; no ligula or inter- mediate branchia above neuropodium Spionidae. mm. Notopodia represented bj' dorsal branchiae in the bases of which the setae are concealed; no laminae caudad of setigerous rami; a ligula or branchia just above each neuropodium of the first seven pairs. A pisthobranchidae. kk. No such palpi present on the prostomium. I. Body with a distinct thorax of nine to fourteen somites "in which the parapodia are uniramous and bear only simple hastate or lanceolate setae or paleae; the remaining part of body ha\'ing parapodia biramous with neuropodia in the form of uncinigerous tori, this region in most with its anterior five, or less commonly but two, somites differentiated into a median region Chaelopteridae. II. Not so. m. Integument in considerable part strongly roughened or tesselated. Body short; somites annulated; branchiae when present few and anterior in position Scalihregmidae. mm. Integument not thus roughened; branchiae when present more numerous. 11. Branchiae none; cirri, excepting certain special anterior ones, very short and stumpy, two-jointed Pisionidae. nn. Branchiae present; cirri when present not of this form. 0. Setae and branchiae throughout strictly lateral in position; body short, of few somites, these commonly annulated. . . .OpheUidae. 00. Branchiaedorsalor subdorsal in position; body elongate, consisting of numerous, short, simple somites. p. Parapodia present as distinct setigerous prominences; cirri present. Body flattened dorsally, rounded ventrally; bran- cliiae usually ligulate. q. Setae strongly cross-striate or annulated; no crochets in posterior region; anal cirri two or four Ariciidae. qq. Setae not annulated; crochets in posterior region; cirri three. Paraonidae. pp. No distinct setigerous or parapodial prominences and no cirri; body convex dorsally; branchiae long and filiform and present on many or a considerable number of somites. .Cirrahdidae. i. Prostomium bearing true tentacles or palpi of ordinary form, or both tentacles and palpi. j. Notopodial setae blade-hke, strongly cross-striate, and arranged in radiate or palmate groups along each side of the dorsum which they cover wholly of in part. k. Notopodia, at least in part, with capillary setae as weU as paleae; noto- cirri on somites separated by one or more not bearing them . . Palmyridae. kk. Notopodia with paleae exclusivelj-; notocirri on all parapodia. Chrysopetalidae. jj. Parapodia not thus differing in character on alternate somites; notopodial setae not of this structure and arrangement. k. Both notopodium and neuropodium bearing a conspicuous lamella on its edge in addition to the cirrus; notopodium also bearing a branchia which is cirriform. 22 THE ANNELIDA POLYCHAETA. Prostomium reduced, mostly quadrangular or rhomboidal with one or two pairs of smaU tentacles on its anterior margin Neplhydidae. kk. Parapodia without such lamella on its rami; branchiae never cirriform, but arborescent, pennatifid or none. /. Mouth shifted caudad and bordered by several similarly formed somites; prostomium often appearing as a dorsal caruncle extending over several somites Amphinomoidea. m. Branchiae none Spintheridae. mm. Branchiae present. n. Setae and arborescent branchiae forming a broad band on each side of the dorsum over its entire length, leaving naked only a narrow stripe along the middle Euphrosynidae. nn. Branchiae and setae not forming such broad dorsal bands. Amphinomidae. II. Mouth not thus shifted back and bordered by several similar somites; prostomium not forming a dorsal band or caruncle; branchiae never in connection with parapodia. VI. Integument roughened, strongly papillose; with numerous short branchiae on peristomium Chlorhaemidae. mm. Integument smooth or at least not papillose; branchiae none. n. Cirri flattened, foliaceous, and usually containing conspicuous mucus glands. 0. Cirri fastened near their middles, elytriform. Prostomium conical and with a single median process; no eyes; fused with the peristomium which bears a pair of cirri Ty phloscolecidae . 00. Cirri not elytriform; prostomium not fused with the peristomium; eyes present Phyllodocoidea. p. Eyes very large; nuchal organs rudimentary or absent; uni- formly five tentacles present; tentacular cirri three or five pairs; pelagic fonns Alciopidae. pp. Eyes small or but moderate, as in most polychaetes, or rarely none; nuchal organs well developed. q. Proboscis with two pairs of true jaws; two pairs of tentacles; no palpi; one pair of tentacular cirri Lacijdoniidae. qq. Proboscis without true jaws, being either wholly unarmed or with a number of small chitinous pieces or denticles, r. A pair of palpi present; tentacles none or a single pair; ex- clusively pelagic forms. s. Tentacles none; parapodia normal lospilidae. ss. A pair of tentacles present; parapodia greatly elongate. Pontodoridae. rr. ^^'ith no palpi. s. Tentacles two pairs and in addition often an unpaired tentacle present; eyes and composite setae nearly always present Phyllodocidae. ss. Tentacles three; eyes none; setae all simple. .Otopsidae. nn. Cirri not flattened or lamellar and not containing conspicuous mucus glands. 0. Palpi massive, two-jointed, with the terminal article small, in- serted well caudad of the pair of tentacles; proboscis consisting of two distinct rings, the distal one of which always bears a pair of maxillae curved toward each other and toothed on the mesal edge ; cirri and tentacles simple Nereidae. 00. Palpi either absent, or when present inserted nearly at the same level as the tentacles, and when biarticulate with the terminal article conspicuously long; proboscis not divided into two suck rings and bearing stout maxillae of this character; cirri and tentacles commonly in whole or in part composed of separate articles, annulated or moniliform Sylloidea. AMPHINOMIDAE. 23 p. Body commonly filiform and most often colorless; palpi never biarticulate; tentacular cirri one or two pairs SijUidne. pp. Body typically short and plump and consisting of from twenty to forty somites, rarely more, and often conspicuously colored; palpi usually evidently, biarticulate; tentacular cirri from six to eight pairs, rarely two pairs or none Hesionidae. a. Prostomium more or less completely hidden by the peristomium; palpi greatly developed and subdivided to form branchiae. Body subdivided into thorax and abdomen, with the notopodia of the abdomen bearing uncini. 6. With a pair of well-developed tentacles; peristomium very strongly developed and forming a bilobed hood each lobe of which bears two or three semicircles of peculiar, stout, usually golden yellow, setae or paleae, or these rarely almost obliterated; thorax of five or six somites. Sabellariidae. 66. Tentacles very small; peristomium not of this form and without cirri or setae Serpuloidea. c. Nearly always with a well-developed thoracic membrane, formed by the fusion of cirri, and an operculum; tube formed of mucin impregnated with calcareous matter, opaque, or rarely translucent Serpvlidae. cc. Without thoracic membrane and operculum; tube formed of mucin of variable consistence and more or less transparent, strengthened or not with mud, sand, pieces of shell, or other foreign material Sabellidae. Amphinomidae. The members of this family have most commonly an elongate body more or less tetragonal in cross-section, less conmionly depressed and subelliptic in outline. Colors nearly always brilliant, often showing as shades of green, scarlet, violet, or yellow. The prostomimn is rounded and is bordered or almost surrounded by the first somites. It bears a pair of palpi and one, three or five tentacles and may or may not bear a dorsal caruncle or nuchal body. Eyes normally four but sometimes two or wholly absent. The mouth is ventral in position and is somewhat removed from the ante- rior end, being bordered by a number of the anterior somites. Parapodia biramous, with one or two dorsal cirri and one ventral cirrus on at least part of them, though these may be rudimentary or absent on others. Branchiae present, each a smgle, mostly arborescent or pennatifid tuft, never in transverse series. Setae simple, capillary or sometimes as stouter hooked spines; in part calcareous and as a result very brittle. Pygidimn with one or two processes which are but little developed; anus dorsal, commonly large. Proboscis protrusible, bearing neither jaws, teeth, or papillae. The amphinomids, while occurring in the colder regions, apparently attain their largest development in warmer parts of the world, such as the Polynesian 24 THE ANNELIDA POLYCHAETA. area, where they abound on the coral reefs, in the Philippines, and in the West Indies. They occur especially in the Uttoral zone and at moderate depths, though they have been taken as far down as 1525 fms. (e. g., Chloenea atlantica Mcintosh. See Challenger Annelida, 1885). These animals are sluggish in movement, showing a marked tendency toward a sedentary and in some cases a parasitic life, and conceahng themselves in retreats which they rarely leave. Many species live in large part upon sponges, among which they liide. They also eat diatoms and radiolarians and other forms occurring in fixed localities. The nutritive value of the food being low necessitates the ingestion of an excep- tional quantity and this is correlated with an anal opening of unusual size. (Cf. Gravier, Nouv. arch. Mas. hist, nat., 1901, ser. 4, 3, p. 239). Some forms are frequently found attached to floating wood or other objects far from land. Such a form is notably Amphinome vagans Savigny (p. 27), which has been taken in chift in various parts of the Pacific and Atlantic Oceans. The Amphinomidae (sens, str.) have not been represented in the collections of the important exploring expeditions by large numbers of species excepting in those of the Siboga in which Horst found no fewer than twenty-two species. Grube mentions five species from the Philip'pines in the Annulata Semperiana, listing four secured by the Gazelle, and tliree in the Annulata Oerstediana. The Challenger secured nine species, this comparatively small number being attributed by Mcintosh to the fact that but Uttle Uttoral collecting was done. But, on the other hand, in the large collection of annelids secured by the Ham- burg expedition to southwestern Australia and coming almost exclusively from the Uttoral zone or from moderate depths, there are but two species of amphino- mids, while Ehlers in his Neuseeliindische Amieliden Usts none at all, as is also the case in that author's report on the polychaetes of the Hamburger Magal- haenische Sammelreise. Ehlers gives two species as found on the Patagonian shores, and includes five in his Florida annelids. Of the polychaetes collected by the Blake in the West Indies, Augener lists three species as belonging to this family. In the Albatross collection from the Hawaiian Islands (1902) Tread- well found five ampliinomids. In his Polychaeta of the Indian Oceap Potts lists thirteen species. Izuka mentions but three species as known from Japan, and Mcintosh in his monograph of British anneUds includes but two. In the present collection there are five species, of which two are widespread and well- known forms, two uncommon, and one new. NOTOPYGOS. , 25 Key to Genera. a. Branchiae arborescent. 6. With no caruncle, c. Branchiae only on the anterior somites; dorsal and ventral cirrus present on the first parapodia, rudimentary on others Paramphinome Sars. 66. With a caruncle. c. Caruncle much reduced. d. Neuropodial setae bifurcate. e. Caruncle of three small lobes in a transverse row, not extending beyond the first somite and preceded by a median tentacle; eyes none Benthoscolex Horst. ee. Caruncle a flexuous crest with short lateral folds, reaching third or fourth somite; eyes present Eurijlhoe Kinberg. dd. Neuropodial setae not bifurcate, simply hooked. Caruncle tongue-shaped or cordiform; notopodial setae partly serrate along two sides, harpoon-shaped, partly more elongate, spinose Amp/iireome Bruguiere. cc. Caruncle well developed. d. With dorsal cirrus single. e. Caruncle without crest or folds, a few transverse grooves, narrowed caudad; eyes none. Sangiria Horst. ee. Caruncle not so. /. Caruncle very large, heart-shaped, with the lateral branches diverging caudad. Pherecardia Horst. //. Caruncle of more moderate size, not cordate. g. Caruncle with lateral branches diverging cephalad Hennodice Kinberg. gg. Caruncle not so. h. Dorsal setae harpoon-like, a double series of retrorse teeth; caruncle with lateral branches diverging caudad Pherecardites Horst. hh. Dorsal setae simply bifurcate; caruncle weakly transversely plaited, true lateral branches not evident; branchiae small, with few filaments. . . .Parachlocia Horst. dd. With a dorsal and an intermediate cirrus Notoptjgos Grube. 6. With no caruncle HippoTioe Audouin and Edwards. 66. With a caruncle. c. With a single dorsal cirrus. d. Eyes present; neuropodial setae smooth Chloeia Savigny. dd. No eyes; neuropodial setae coarsely serrate along inner border .... Bathychloeia Horst. cc. With a dorsal cirrus and an intermediate cirrus Chloenea Kinberg. Synonyvnj of Genera. Didymobranchus Schmarda is too imperfectly known at present to be placed with certainty. Eucamnculata Malaquin and Dehorne (1907) is synony- mous with Pherecardia Horst (1886). Cryptonota Stimpson and Oniscosoma Sars are the same as Spinther Johnston, type of the amphinomoid family Spintheridae, not represented in the present collection. NoTOPYGOS Grube. Archiv. naturg., 1855, 21, p. 93; Annulata Semperiana, 1878, p. 7. Lirione Kinberg, Ofvers. K. vet. akad. Forh., 1857, 14, p. 12. Notopygos was used by Grube in 1850 in his tjbersicht der annehdengat- tungen und arten (p. 21) but without mention of any species, and again in 1851 26 THE ANNELIDA POLYCHAETA. in his Fainilien der anneliden (Archiv. naturg., 16, p. 40); but as he gave no diagnosis either for the genus or its type-species at that time, the genus must date from 1855. NoTOPYGOS MACULATA (Kinberg). Lirione maculata Kinberg, Ofvers. K. vet. akad. Forh., 1857, 14, p. 12; Baird, Journ. Linn. soc. London. Zool, 1868, 10, p. 226; Kinberg, Fregatt. Eugenies Resa Zool. Annulater, 1910, pi. 11, f. 5-5x. Notopygos maculata Grube, Annulata Semperiana, 1878, p. 8, pi. 1, f. 3; Malaquin & Dehorne, Rev. Suisse zool., 1907, 15, p. 357. Locality. Panama: Taboguilla Island. 31 October, 1904. One specimen taken on the shore. It is only about 10 mm. in length, or half that of the type, and is evidently not in full color. The specimen is topotypical, Kinberg stating of the type "Hab. oras insularum juxta Panama." Hermodice Kinberg. Ofvers. K. vet. akad. Forh., 1857, 14, p. 12. Hermodice striata Kinberg. Ofvers. K. vet. akad. Forh., 1857, 14, p. 13. Hermodice pennata Treadwell, Bull. U. S. fish comm., 1903, 23, pt. 3, p. 1165. Locality. Society Islands: Papeete. 9 November, 1899. Two speci- mens taken on the shore. These specimens, the larger of which is complete and 23 mm. in length, agree fully with the original description. The type was also from the Society Islands, having been taken on the coral reef at Eimeo. The somites are conspicuously marked above by longitudinal stripes of brownish pink which extend part way or entirely across each somite. The distal end of the notopodia is encircled with dark. The setae are whitish. The setae agree in structure with Kinberg's account. The head, tentacles, caruncle, and cirri have the characteristic structure described by Treadwell for his H. pennata which seems without doubt to be the same species. Amphinome Bruguiere. Encyclop. method., 1789, 1, p. viii, 44; 1791, 7, p. 88; Cuvier, Diet. sci. nat., 1804, 2, p. 3113; Horst, Siboga exped. Monog. 24a, 1912, p. 39. Pleione Savigny, Descript. Egypte. Hi.st. nat., 1809 [= 1822], 1, pt. 3, ]). 14, 59; Cuvier, Regno anim., ed. 2, 1829, 3, p. 199. EURYTHOE. 27 Amphinoma Blainville, Diet. sci. nat., 1828, 57, p. 450; Audouin & Milne Edwards, Hist. nat. litt. France. Annelidcs, 1831, 2, p. 121. Linopherus Quatrefages, Hist. nat. anneles, 1865, 1, p. 392. Leiiora Geube, Annulata Semperiana, 1878, p. 2. Amphinome vagans (Savigny). Pleione vagans Savigny, Descript. Egypte. Hist, nat., 1809 [ = 1822], 1, pt. 3, p. 60. Amphinoma vagans Bl.unville, Diet. sci. nat., 1828, 67, p. 451; Audouin & Milne Edwards, Hist. nat. litt. France. Annelides, 1834, 2, p. 122. Amplmiome vagans Grube, Arehiv. naturg., 1850, 1, p. 289; Kinberg, Of vers. K. vet. akad. Forh., 1857, 14, p. 12; Quatrefages, Hist. nat. anneles, 1865, p. 403; Baird, Journ. Linn. soc. London. ZooL, 1870, 19, p. 218; McIntosh, Challenger Annelida, 1885, p. 24; Horst, Notes Leyden mus., 1886, 8, no. 3, p. 159; Kinberg, Fregatt. Eugenies Resa. Zool. Annulater, 1910, p. 34, pi. 11. fig. 6. Pleione tetraedra Milne Edwards (nee Savigny), Regne anim. illust. Annelides, 1849, pi. 8, fig. 1, la. Amphinome rostrata Kinberg (nee Pallas), Ofvers. K. vet. akad. Forh., 1857, 14, p. 12; McIntosh, ChaUenger Annelida, 1885, p. 21, pi. lA, fig. 16, pi. 2A, fig. 8-12; Andrews, Proe. U. S. N. M., 1891, 14, p. 278; IzuKA, Journ. Coll. sci. Imper. univ. Tokyo, 1912, 30, p. 226, pi. 1, fig. 2, pi. 22, fig. 6-9. Amphinome pallasii Quatrefages, Hist. nat. anneles, 1865, p. 394; Baird, Journ. Linn. soc. London. Zool., 1870, 19, p. 218; Ehlers, Mem. M. C. Z., 1887, 15, p. 26, pi. 1, fig. 4; Moore, Proc. Acad. nat. sci. Philad., 1903, p. 793; Fauvel, R6su1. campag. sci. Prince Monaco, 1914, 46, p. 85. Localities. Off Marquesas Islands. Sta. 3686 (lat. 12° 20' S; long. 144° 15' W.). Surface temp., 79° F. 19 September, 1899. One specimen 22 mm. long taken on barnacles diifting at surface. Off Acapulco Light House, Mexico. Sta. 4596 (lat. 16° 48' N., long. 100° 27' W.). Surface temp., 84° F. 14 October, 1904. Six immature specimens ranging in size from only 2.5 mm. to 8.5 nmi. were taken from driftwood. This species has often been taken similarly from driftwood elsewhere in the Pacific as well as in the Atlantic. The specimens recorded agree in details of structure of the setae and other parts with specimens from the Atlantic excepting, in the case of those from the second locality, in slight points such as the difference in size and form of the knob on the shortest setae, differences possibly due to immaturity. The largest of the specimens from Sta. 4596 has twenty-five somites, the smallest seventeen, the most caudal of these being short and closely crowded. The forms that have usually been referred to A. vagans seem without doubt to be partly grown specimens of the same species known as A. pallasii and, in part, as A. rostrata. The true rostrata is a species occurring in the Indian Ocean and differing from the Atlantic and Pacific form that has been Usted under that name; vagans has priority over pallasii. EuRYTHOE Kinberg. Ofvers. K. vet. akad. Forh., 1857, 14, p. 13. 28 THE ANNELIDA POLYCHAETA. EURYTHOE COMPLANATA (Pallas). Plate 14, fig. 3-8 Aphrodite complanata P;Vllas, Misc. zool., 1766, p. 109, pi. 8, fig. 1926. Pleione complanata Savigny, Descript. Egypte. Hist, nat., 1809 [= 1822], 1, pt. 3, p. 62. Pleione alcyonia S.wigny, Descript. Egypte. Hist, nat., 1809 |= 1822], 1, pt. 3, p. 62, pi. 2, fig. 3. Eurythoe pacifica Kinberg, Ofvers. K. vet. akad. Forh., 1857, 14, p. 14; Grube, Novara Annelid., 1867, p. 8; Monatsb. K. preuss. akad. wiss. Berlin, 1877, p. 509; Annulata Semperiana, 1878, p. 6; McIntosh, Challenger Annelida, 1885, p. 27; Malaquin & Dchobne, Rev. Suisse zool., 1907, 15, p. 357; Kinberg, Fregatt. Eugenics Resa. Zool. Annulater, 1910, pi. 12, f. 11. Eurythoe kamchamecha Kinberg, Ofvers. K. vet. akad. Forh., 1857, 14, p. 14; Ehlers, Zool. jahrb. Syst. 1905, 22, 3, p. 281; Kinberg, Fregatt. Eugenics Resa. Zool. Annulater, 1910, pi. 12, f. 13. Eurylhroe corallitui Kinberg, Ofvers. K. vet. akad. Forh., 1857, 14, p. 14. Eurythoe complanata Langerhans, Nova acta Acad. Caesareae Leop. Carol., 1881, 42, p. 108. Ehlers, Mem. M. C. Z., 1887, 15, p. 29; Nach. K. gesellsch. wiss. Gottingen, Math. phys. klasse, 1897, p. 159; Festsch. K. gesellsch. Gottingen, 1901, p. 34; Treadwell, Bull. U. S. fish comm., 1901, 20, pt. 2, p. 194; Collin, Polych. Amboina etc., 1902, p. 99; Ehlers, Zool. jahrb. Syst., 1905, 22, 3, p. 281; Deutsch. tiefsee exped. Valdivia, 1908, 16, p. 38; Pott.'!, Polych. Indian Ocean, 1909, pt. 1, p. 307; HoRST, Siboga exped. Monog. 24a, 1912, p. 34, pi. 9, fig. 20; Augener, Fauna Siidw.-Austr. Polych., 1, 1913, 4, 4, 6, p. 87. Eurythoe pacifica var. levukaensis FiscHLi, Abh, Senck. naturf. gesellsch. Frankfurt-a-M., 1900, 25, p. 98. Eurythoe alcyonia Gravier, Nouv. arch. Mus. hist, nat., 1901, ser. 4, 3, p. 248. Localities. Paumotu Archipelago: Rangii'oa. 23 September, 1899. Three small specimens. Paumotu Archipelago: Fakarava. 13 October, 1899. Eighteen specimens taken on the fringing reef, a few of these being immature. Paumotu Arcliipelago : Makemo. 21 October, 1899. Numerous young specimens. Society Islands: Papeete. 9 November, 1899. Shore. Two small speci- mens. Society Islands: Bora Bora. 17 November, 1899. Fringing reef. Numer- ous young and partly grown specimens. Easter Island. 20, 21 December, 1904. Three specimens from the shore. Galapagos Islands: Chatham Island. 8, 9 January, 1905. Shore. Three specimens. Eurythoe com-planata as here accepted has an almost cosmopolitan distri- bution in the warmer latitudes. It is abundant and very widespread on the coasts of the Indo-Pacific region from East Africa and the Red Sea to the Phil- ippines, Hawaiian Islands and the Galapagos, without, however, having been taken on the western American coast, and it occurs as well in the Atlantic in the West Indies and on the African coast at the Canaries, etc. On the west coast of America it is represented by a smaller but very closely related form, E. paupera Grube {E. californica Johnson) which occurs in the littoral zone EURYTHOE COMPLANATA. 29 from Patagonia northward to California. It seems to be extremely abundant on the coral reefs of the Pacific Islands. E. complanata was described originally from the West Indies, E. alcyonia from the Red Sea, and E. pacifica from the Society Islands (Eimeo); but the forms identified by different \\Titers under these three names overlap extensively in their ranges and at the same time present no distinctive morphological characters that have been thus far pointed out. Shght differences in the setae occm- in specimens from many different localities; and it is quite Ukely that after the minute study of abundant material it will be possible to limit various local varieties ; but such discrimination seems impossible in the present state of our knowledge. I do not find that the sup- posedly characteristic serrations of the fvucate setae of dorsal and ventral fasciae in E. pacifica are present even in most specimens from the general type- locality. E. coralUna Kinberg I regard as having been based upon young speci- mens of this species, the number of buccal segments having been found to vary with age. Specimens from all the locaUties mentioned agree in general form and pro- portions, the body having a flattened form of subrectangular cross-section about t^vdce as vAde as high. The oval prostomium has four eyes; the tentacles are short, wdth the median shorter than the lateral and scarcely as high as the adja- cent caruncle. The caruncle does not extend beyond the fourth segment. There are three or four buccal segments. Both the dorsal and the ventral cirri are shorter than the setae and are jointed. Notopodial setae include besides the prevalent straight serrate tj^pe, a very slender furcate type, the branches of which are fine. The nem-opodial setae are of a much stouter furcate type in wliich the branches are stout. In both furcate types serrations may or may not be present. While the setae vary obviously in form, it does not seem possible at present to define varieties or subspecies on this basis. (See Plate 14, fig. 3-9). The specimens from the Galapagos conform in the features above mentioned. The midventral line is dark as in many specimens from the Paumotus, etc.; but, in addition, there is a slight darkening in a narrow band adjacent to the parapodia both above and below. The dorsal sm-face is more strongly sulcate and roughened than usual. The smallest specimen is 53 mm. long and 6 mm. wide, exclusive of the setae. It is composed of seventy somites. The inter- mediate specimen is nearly 100 mm. long, has a maximum width of 11 mm. and embraces one hmidred and two somites. The third specimen is much larger and greatly exceeds other specimens of the species of which I find measure- ments recorded, and presents a correspondingly large number of somites. It is 30 THE ANNELIDA POLYCHAETA. 350 mm. long, has a maximum width, exclusive of setae, of 15.5 mm. and inclu- sive of setae of 20 mm. It consists of one hundi-ed and eighty-four somites or near that number. Chloeia Savigny. Descript. Egypte. Hist, nat., 1809 [= 1822], 1, pt. 3, p. 58. Cloeia Savigny, Descript. Egypte. Hist, nat., 1809 [ = 1822], 1, pt. 3, p. 14. Chloeia entypa, sp. nov.' Plate 13, fig. 8, 9; Plate 14, fig. 1, 2. The general color of the body is yellowish throughout ; the setae a brighter, uniform yellow; the dorsal cirri deep violaceous or purplish, becoming more dilute distad. The body is narrower caudad, being narrowly obovate in outline. The length is near 10 mm. and the greatest width, exclusive of the setae, is about 4.2 mm. ; the longest setae measure 3.2 mim. There are twenty-three or twenty- four somites (or twenty without the cauda). The anterior paired tentacles are widely separated at the base; they are paler in color and about two thirds as long as the posterior ones. The pos- terior paired tentacles are inserted close together immediately in front of the anterior end of the caruncle; they are shorter than the median tentacle which in turn is only about half as long as the caruncle. All the tentacles are of the usual subulate type. None has any dark pigmentation. The elevated caruncle is attached in front to the first two somites but extends caudad to the fifth where it ends freely. It narrows continuously from the anterior end to the posterior. It is doubly crenate or foliate as usual, there being in the type eight to ten pairs of foliae. The color is yellow throughout with no dark markings. The mouth is a simple opening. From it there extends forward and about the anterior end the usual two connate palpal ridges. It ends at the third somite which on the ventral side is longest at the middle with the median region longi- tudinally wrinkled. The typical segments of the body have the usual general structure. Ven- trally the somites show many longitudinal impressed sulci and along the mid- ' (frvwos, impressed. CHLOEIA ENTYPA. 31 ventral line a sharply defined, wide, depressed band or neural channel. The branchiae are large. Each one normally extends caudad much as in C. maculata Potts, but is much longer, typically overlapping the succeeding somite and branchia. The branches from the main trunk of the branchia are relatively long and numerous; they may bear a few secondary branches or pinnulae but the more distal ones are more commonly simple. The dorsal cirri are very conspicuous because of their strongly contrasting deep violaceous color. Each is attached caudad of the notopodial tubercle as usual. They are distally slenderly subulate and in the preserved specimen are shorter than the long ventral setae. The ventral cirri are pale throughout and are slenderly subulate. Each is attached on the caudoventral side of the ventral fascia. The dorsal setae are distinctly coarser than the ventral. The prevailing type is moderately curved and has the furcate apical part more or less at an angle with the proximal division. The larger distal branch is long and acute, the shorter branchy or spur being parallel with it excepting the tip which curves slightly outward or away from the axis. (Plate 13, fig. 8). The principal branch is prevaiUngly smooth along both edges. A second type occurs in the middle and especially the posterior region. The setae of this type are coarser. The outer edge of these setae is very finely serrulate, the teeth being minute and occurring chiefly on the distal half. (Plate 14, fig. 1). None of the setae show such coarse teeth as occur for instance in C. fiava (Pallas). Only one form of setae was observed in the ventral fasciae. These are finer and longer than the dorsals. In the furcate tip of these setae the main branch is straight and slender with the edges smooth. The spur is short and straight and a Uttle divergent. (Plate 13, fig. 9). Locality. Off Mexico. Sta. 3418 (lat. 16° 31' N., long. 99° 52' 30" W.). Depth, 66 fms. Bottom, brown sand with black specks. Bottom temp., 39° F. Exped. 1891. One specimen. The depth is exceptional for the genus. In general structural features this species approaches the widespread C. flam (Pallas), though it is a much gmaUer form with correspondingly fewer somites. It has the similar conspicuous, purplish brown, dorsal cirri arising from a non-pigmented base, but lacks the other dark markings so conspicuous in flava and does not present the more brightly yellow tips to the setae. The branchiae and setae differ clearly from those of flava in details of form and structure. 32 THE ANNELIDA POLYCHAETA. EUPHROSYNIDAE. These are forms of small or medium size in which the body is oblong or elliptic, with the dorsum in some degree arched and the venter flattened. The number of somites is comparatively small, being mostly between twenty and sixty. The prostomium is small and compressed and bends down anteriorly to the ventral surface. It bears typically four eyes, two dorsal and two ventral, and three tentacles, a median and two lateral ones arising ventrally, or rarely no tentacles present (Lophonta). Palpi adnate at border of mouth. A caruncle present, distinct. Mouth ventral, extending over several somites. Parapodia with rami fused and extending as a transverse ridge upon the dorsum toward the median line, the ridge bearing setae and branchiae. A ventral cnrus and from one to three dorsal cirri present. The branchiae on the dorsal extension of the parapodia are arranged in transverse series, in such manner that with the accompanying setae they leave free only a narrow median longitudinal band. The branchiae are branched, pennatifid, or arborescent. Setae simple, the ventral ones commonly unequally and conspicuously bifurcate distally. Dorsal setae rarely replaced by stout paleae. Pygidium with two processes or an undivided rim. The euphrosynids may occur at considerable depths, but are most frequent in the Uttoral region as with the amphinomids. The genus Lophonta of Costa is insufficiently known. It is placed with Euphrosyne tentatively because of the arrangement of the gills in transverse series. Key to Genera. a. Tentacles absent Lophonta Costa. aa. Tentacles present. h. Only one dorsal cirrus; dorsal setae in the form of large flat paleae. . . . Palmyrcuphrosyne Fauvel. bb. Two (or three) dorsal cirri present; dorsal setae not thus modiSicd. .. .Euphrosyne Savigny. Euphrosyne Savigny. Descript. Egypte. Hist, nat., 1809 (= 1822], 1, pt. 3, p. 63; Audouin & Milne Edwaed.s, Hist. nat. litt. France. Annclides, 183-1, 2, p. 124; Ehlers, Borstenwiirmcr, 1861, p. 61; Gkube, Annulata Semperiana, 1878, p. 11; McIntosh, British annelids, 13D0, 1, pt. 2, p. 233. Euphrosine Cuvier, Regne anim. ed. 2, 1829, 3, p. 199; Blainville, Diet. sci. nat., 1828, 57, p. 199. EUPHROSYNE PANAMICA. 33 EUPHEOSYNE PANAMICA, Sp. nOV. Plate 12, fig. 7, 8; Plate 13, fig. 1-7. The general color of the type is at present yellowish gray. The body in outhne is oblong with the anterior end rounded; narrower from the middle caudad, with the caudal end also rounded; the sides of the anterior region between the middle and the convex anterior end are straight and parallel or nearly so. The total length of the type is nearly 14 mm. and the greatest width over all 6.5 mm. The number of setigerous somites counted in the type is thirty-five. The naked median dorsal stripe is narrow, being only about one sixth the total width in the median region or one fourth excluding the setae. The stripe is smooth. The caruncle is a slender smooth finger-like or cirriform process projecting freely caudad, crossing the fifth somite and in the type touching the anterior border of the sixth. It is acuminate caudad. The unpaired tentacle presents the usual slender, tlu-ead-hke distal article; it scarcely reaches caudad of the middle of the caruncle when laid along the latter. The paired tentacles are much longer than the median and are of about the same thickness and general form as the caruncle and lack a terminal filament; they reach three fourths the distance to the caudal end of the caruncle when laid back along the latter. On the ventral surface of the head the palpi together form a heart-shaped . cushion with the tip forwards. This cushion is longitucUnally divided by a deep furrow. Its surface is whoUy smooth. It is bordered by the first and second somites and is touched caudally by the third. The median fold of the lower lip is cordate in outline with the apex directed caudad. It is much smaller than the lobe formed by the palpi. The apex extends to the middle of the fifth somite. The lobe is crossed by distinct radiat- ing furrows. It is bordered by part of the third and the fourth somites, while its apex extends into the fifth. The branchiae are short, the long setae projecting much beyond their distal ends though not so the shorter ones. On each side of each somite there are for the most part twelve branchiae. The branchiae in each row are closest together at the ectal end of the series and the space between the first and second from the mesal end of the series is distinctly larger than that between any other two. Each branchia presents a short stout trunk wiiich divides typically into two branches which bear the many terminal twigs, each of which ends in a con- 34 THE ANNELIDA POLYCHAETA. spicuous bud-like expansion which is drawn out into an acute point. The branches of adjoining branchiae intermingle so that when a series is viewed from above only a continuous brush-like band appears, the separate branchiae not being distinguishable in dorsal view. The cirri are simple thread-like structures which do not surpass the branchiae in length. The dorsal and lateral or intermediate cirri are similar. The lateral dorsal cirrus is inserted opposite the fourth (or third?) branchia. The dorsal setae extend in transverse series parallel with the row of branchiae entirely across the dorsal ridge to the outermost branchia and are not separated by any distinct empty space from the lateral setae. The principal dorsal setae rise clearly above the tops of the branchiae. Each is forked in the usual way. The principal prong is long and straight or with a weak double curve. The smaller branch curves a Uttle outward. (Plate 12, fig. 3). Both prongs are wholly smooth. In a second type of dorsals the setae are similar excepting for being shorter and finer. (Plate 13, fig. 4). In addition there are characteristic short dorsal setae which are strongly clubbed at the distal end. In these the distal enlargement is cleft from one side in a plane that curves caudad, sepa- rating a lower lobe with convex inner face from an upper one with concave inner surface. The inner surface of each of these lobes is transversely ridged along each border. (Plate 12, fig. 7; Plate 13, fig. 1, 2). Somewhat similar setae exist in E. triloba Ehlers and in E. myrtosa (Savigny). The upper ventral setae are as long as the dorsals, the lowermost much shorter. They are similarly furcate but are rather more slender. As with the dorsals, no teeth occur on the prongs. In the shorter ventral setae the principal prong may have but a single weak curve, or it may be straight and acute; while the minor prong may be reduced to a minute acute tooth. (Plate 13, fig. 5, 6). Locality. Panama: Perico Island. Shore. 26 October, 1904. Two specimens. This species in the general character and number of its branchiae approaches E. capensis Kinberg. The latter is larger (40-50 mm.) with a much larger number of somites (between fifty and sixty). The ventral setae have their prongs serrate instead of wholly smooth. The caruncle is longer, extending over eight somites instead of only five. That species would seem also to lack the characteristic clavate dorsal setae. The present species also has close similarities to E. limbaia Moore ; but in the latter there is but one type of setae, the peculiar cleft clavate form being absent and the branchiae seem not to have the conspicuous, bud-like terminal enlargements. POLYNOIDAE. 35 POLYNOIDAE. In this family the body is flattened and narrow with the sides nearly parallel, or else broader and oval and elliptic and in other cases elongate and more typi- cally vermiform. Prostomium distinct, convex. Facial tubercle absent or weakly developed. Eyes four. Two lateral tentacles and in most cases also a median tentacle present. Palpi present, elongate. First somite, or peristomium, bearing usually setae in reduced number. Two pairs of elongate cirri, the ventral cirrus of the succeeding somite also ordinarily very elongate. Parapodia biramous with ventral cirri and dorsally in part notocirri and in part elytra. Elytra borne on somites II, IV, V, VII and so on, on the odd somite to the twenty third, after which, when elytra occur at all, two cirriferous somites are ordinarily intercalated between two bearing elytra; more rarely the anterior ones on II, IV, VI, VIII, and X. (Hemilepidia). Setae all simple. Dorsal setae with sunple or bifid and more or less hooked tips. Pygidium with two anal cirri. Proboscis distally with a single circle of equal papillae; armed with four horny jaws. The polynoids live under a great variety of conditions, some at considerable depths, but the greater number in shallower water along the shores, among Algae, growths of eel-grass (Zostera), bryozoans, and hydroids, such being various species of Lepidonotus, Polynoe, Halosydna, etc. In contrast with the sluggish movements of most, some swim freely and with considerable agility and gracefulness, e.g., Halosydna gelatinosa M. Sars. (Gravier, Nouv. arch. Mus. hist, nat., 1901, ser. 4, 3, p. 206) and a few forms, such as Drieschia pelagica Michaelsen, Nectochaeta, and Plotolepis, gen. nov., are pelagic. Many are commensals, different forms living in association with sponges (e.g., Lagisca hexactinellidae and Polynoe eupledellae occurring in Eupledella aspergillum and having a corresponding remarkable transparency); coelenterates {e.g., Polynoe ruiilans Grube, occurring on and matching in coliy an alcyonarian, Xenia); starfishes, many polynoids placing themselves in the ambulacral grooves near the mouth and apparently there securing fragments of food escaping the star- fish (e.g., the well-attested case of Acholoe astericola Delle Chiaji occurring on Astropecten aurantiacus (Linne), A. bispinosus (Otto), A. irregularis (Pennant), 36 THE ANNELIDA POLYCHAETA. and probably others, Harmothoe lunulata also occurring on the latter) ; ophiurans (e.g., Scalisetosus communis on Ophiothrix alopecurus Miiller & Troschel and 0. fragilis (Abild.)); sea-urchins (e.g., Scalisetosus echini on Echinus esculentus Linne to which it presents a clearly mimetic resemblance and Hololepidella commensaUs Willey on Clypeaster humilis Ceylon pearl oyster fisheries report, 1905, pt. 4, p. 251); holothurians {e.g., Lepidasthenia pulchra Johnston on Stichopus calif ornicus (Stimpson) which it matches in color); molluscs {e.g., this same Lepidasthenia pulchra occurring in the cavity between mantle and foot in Lucapina crenulata); other annelids, this group and that of the echino- derms being the ones which bear polynoids in greatest numbers, these having been noted in association with serpulids, terebellids, arenicolids, chaetopterids, cirratulids and even eunicids, an interesting case being that noted by Webster in which Harmothoe parasitica fives under the elytra of Lepidametria commen- saUs which in turn is itself parasitic on Amphitrite ornata (Trans. Albany insti- tute, 1879, p. 9) ; Enteropneusta {Lepidasthenia digueti Gravier in association with a Balanoglossus from the Gulf of Cafifornia cf. Gravier, Bull. Soc. philom., 1905, ser. 9, 7, pt. 3, p. 160) ; and tunicates {e.g., Herdmanella ascidioides Mcin- tosh) , in the branclual chamber of an ascidian, probably a Styela, see Darboux, Bufi. sci. France & Belgique, 1900, 30, p. 11, etc.). As with the aphroditids, the polynoids frequently themselves bear various other animals, including protozoans, sponges, coelenterates, bryozoans, other annefids, and Crustacea, some members of which seem to be the parasites most common {e.g., species of Sefius, Silenium, and Selioides, see St. Joseph, Ann. sci. nat., 1888, ser. 7, 5, p. 141). Like other aphroditoids, the polynoids are carnivorous, feeding upon such forms as sponges, hydroids, other annelids and crustaceans and more rarely small moUuscs. Of very great interest in the present Albatross cofiection are tfie pelagic members of the Polynoidae which add four species, including three new genera, to the six species previously knowTi. The ten forms are as fofiows : — 1. Polynoe pelagica Viguier Arch. zool. exper., 1886, ser. 2, 4, p. 416. Medi- terranean. 2. Polynoe innatans, sp. nov. Eastern south Pacific. 3. Nectochaeta grimaldi Marenzeller, Bull. Soc. zool. France, 1892, 17, p. 183. North Atlantic. 4. Harmopsides natans, gen. et sp. nov. Coast of Peru and at several stations northward to the latitude of Central America. POLYNOIDAE. 37 5. Drieschia pelagica Michaelsen, Jahrb. Hamb. ^^^ss. anstal., 1892, 9, p. 6, fig. 15-18. Off Ceylon. 6. Plotolepis nans, gen. et. sp. nov. Pacific near Easter Island. 7. Plotolepis pellucida (Moore), Proc. Acad. sci. Phil., 1903, p. 794, pi. 50, fig. 1-12. From the Atlantic ofT Massachusetts. 8. Podarmus ploa, gen. et sp. nov. Pacific off Easter Island. 9. Quetiera pelagica Viguier, Ann. sci. nat., 1911, ser. 9, 13, p. 252; 1912, ser. 9, 15, p. 89, pi. 2, 3, f. 1-6. Mediterranean. 10. Frenna dubia Viguier, op. cit., 1912, ser. 9, 15, p. 94, pi. 2, 3, f. 11. MecUterranean. Ehlers thinks it possible that his Herdmanella gracilis from off the African coast is a pelagic form ; but this is uncertain as it was among forms secured at depths from 1,500 to 2,000 meters in the vertical net. (Deutsch. tiefsee-exped. Valdivia, 1908, 16, p. 44, pi. 5, f. 1^). Key to Genera. a. With only two tentacles. b. With a facial tubercle; notopodial setae finer than the neuropodials. c. Eyes present; elytra with surface in part papillose Iphione Kinberg. cc. No eyes; elytra smooth Iphionella Mcintosh. 6&. No facial tubercle; notopodial setae coarser than the neuropodials Bylgides, nom. nov. aa. With three tentacles. b. Lateral antennae inserted at margin of prostomium. c. Pelagic forms; these comparatively short, colorless and transparent; setae ordinarily con- spicuously elongate or of a special natatory tj-pe. d. Parapodia strictly uniramous, the notopodium represented by neither lobe, aciculum or setae. e. Notocirri unequally developed, those of the anterior region and alternate ones in the posterior region decidedly elongate and more or less inflated. . . .Plotolepis, gen. nov. ee. Notocirri not thus very unequally developed. /. Setae of one type, fine, capillary, and long. g. Neurocirri attached near the middle of neuropodium or proximad of it, the first elongate but all others very small, falling clearly short of attaining the distal end. Quetieria Viguier. gg. Neurocirrus attached far distad of middle of neuropodium, the distal end of wliich it much surpasses Frenna Viguier. //. Setae of two forms, one long and fine and the other shorter and stouter, all with tips entire. g. Parapodia all with a conspicuous, though short, cylindrical or somewhat clavate process from posterior surface just above insertion of neurocirrus; coarser ventral setae straight, nearly as long as the dorsals and equally as numerous. Podarmus, gen. nov. gg. Parapodia with no such process from the caudal side; coarser ventral setae much fewer and verj' much shorter than the finer dorsals, and more or less sigmoidally curved Drieschia Michaelsen. dd. Parapodia biramous. e. With a median process or "sub tentacular cirrus" beneath the median tentacle; no noto- podial setae; pairs of elytra eighteen Harmopsides, gen. nov. ee. With no sub tentacular cirrus; in each notopodium a stout seta in addition to the aciculum; pairs of elj^tra eleven Nectochaeta Marenzeller. 38 THE ANNELIDA POLY€HAETA. cc. Non-pelagic forms; these pigmented and more or less opaque; setae ordinary. d. Elytra arranged in the usual manner in the family. e. Somites more or less numerous, with the body long and vermiform; notopodia abortive, with its setae few or none; elytra commonly much reduced in size. /. Ventral cirri bearing conspicuous wart-like tubercles Perolepis Ehlcrs. ff. Ventral cirri as usual, smooth. g. Elytra occurring in pairs tliroughout Lepidasthenia Malmgren. gg. Certain somites having an elytron on one side paired with a cirrus on the other. Lepidameirea Webster. ee. Body mostly short and depressed, proportionately broader, and somites fewer. /. First pair of elytra of normal size, all others exceedingly small; elytra twelve pairs; no notopodial setae Hermenia Grube. //. Elytra not thus. g. Median tentacle inserted dorsally. h. Inserted on the anterior region of the prostomium; notopodial setae coarser than the ventrals Allmaniella Mcintosh. hh. Inserted on the posterior region of prostomium. i. Parapodia without notopodial setae Admeiella Mcintosh. ii. Notopodial setae present, coarser than the ventrals Macellicephala Mcintosh. gg. Median tentacle inserted marginally. h. With a subtentacular process or " cirrus " ; dorsal setae coarser than the ventrals. Eulagisca Mcintosh. hh. With no such subtentacular process. i. Notopodial setae finer than the neuropodials. j. Prostomium anteriorly with distinct peaks which bear the lateral tentacles. k. With vesicular expansions about bases of elytrophores and cirrophores; pairs of elytra twenty Physalidonolus Ehlers. kk. With no such vesicular expansions. I. Elytra eighteen pairs or more Halosydna Kinbcrg. II. Elytra twelve or thirteen pairs. m. Palpi short and blunt, exceeded by the tentacles; styles of lateral tentacles short and conical; eyes none Bathynoe Ditlevsen.' mm. Palpi and styles normal, tentacles not exceeding the former; eyes present. n. Elytra thirteen pairs Euphione Mcintosh. nn. Pairs of elytra twelve. 0. Notopodial setae with series of pectinae Lepidonohis Leach. 00. Notopodials of two kinds, one wholly smooth . . Thorinora Baird. ]j. Prostomium without such anterior peaks; elytra fifteen pairs. Malmgrenia Mcintosh. ii. Notopodial setae coarser than the ventrals. j. Pairs of elytra eighteen, or more. I. Neuropodial setae with apices bidentate; pairs of elytra eighteen. Alentia Malmgren. II. Neuropodial setae with apices entire; pairs of elytra twenty-one or twenty- two Psetidohalosydna Fauvel. dd. Elytra arranged as usual anteriorly but occurring on all somites in the posterior region. Hololepida Moore. 66. Lateral antennae inserted ventrally. c. Body long and vermiform. d. Elytra completely covering the body; notopodial setae finer than the ventrals. Acholoe Claparede. dd. Dorsum in part uncovered. e. Anterior elytra on somites 2, 3, 4, 6, 8, and 10 Hemilepidia Schmarda. ee. Anterior elytra as usual, on somites 2, 4, 5, 7, 9, and 11. /. No notopodial setae; neuropodials with tips entire Heteropolynoe Bidenkap. //. Notopodial setae present. •The number of pairs of elytra not definitely stated by Ditlevsen for this genus, but presumably as in Lepidonotus. Cf. Danish Ingolf-Expcd., 1917, i, pt. 4, p. 42. POLYNOIDAE. 39 g. Elytra fifteen pairs, all in the anterior region; notopodial setae commonly finer than the neuropodials. h. Prostomium rounded anteriorly, without peaks Enipo Malmgren. hh. Prostomium with anterior peaks. i. Neuropodial setae distally bifid; notopodials with transverse rows of spines or pectinae Polynoe Savigny . ii. Neuropodial setae distally entire; notopodials simply serrate . Nemidia Malmgren. gg. Elytra not thus confined to the anterior region; notopodials not finer than the neuro- podial setae Polycunoa Mcintosh. Body short and more or less depressed, more rarely sublinear. d. Dorsum normally completely covered with the elytra. e. Median antenna inserted at the margin. /. Parapodia uniramoas Polynoella Mcintosh. //. Parapodia biramous. g. Notocirri alternately short and long; dorsal setae stouter than the ventrals. Kermadecella Darboux. gg. Notocirri all of the same length. h. Notopodial setae of same thickness as the neuropodials Intoshella Darboux. hh. Notopodials not of same thickness as the neuropodial setae. i. Notopodials stouter than the neuropodials, or at least equal to them. j. Notopodials smooth Meloenis Mcintosh. jj. Notopodials with transverse rows of spines. k. Body linear or sublinear; tips of neuropodial setae wholly straight, bifid, with the incision very fine Eucranta Malmgren. kk. Body elliptic or ovate oblong; tips of neuropodials obviously more or less curved, when bifid the teeth diverging. I. Elytra sixteen pairs Leucia Malmgren. U. Elytra fifteen pairs. TO. Elytra smooth Laenilla Malmgren. mm. Elytra granular or scabrous. n. Anterior eyes situated on the peaks, small, ventral or subventral; peaks close to the median tentacle Harmothoe Kinberg. nn. Anterior eyes farther caudad, larger, lateral in position; peaks usually well separated from the median tentacle. 0. Neuropodial setae with tips entire. p. Tips of neuropodials long and fine Antinoe Kinberg. pp. Tips of neuropodials short, not hair-like. 5. Head very broad; ceratophore of median tentaele ex-tends between peaks caudad of middle of prostomium; anterior eyes much larger than the caudal .... Phyllaniinoe Mcintosh. gq. Head not unusually broad, and ceratophore of median an- tenna not extending caudad of middle. . . .Eunoe Malmgren. 00. Neuropodials with tips bifid Evarnclla, nom. nov. ii. Notopodials finer than the neuropodial setae, typically in part thread-like distally. j. Notopodials smooth Roherlianella Mcintosh. jj. Notopodials with transverse rows of spines. it. Ventral setae with tips entire GaUyana Mcintosh. kk. Ventral setae with tips bifid Paranychia Czerniawsky. ee. Median antenna not inserted at the margin. /. IMedian antenna inserted dorsally. Notopodial setae of same thickness as the finer of the ventrals, these being of two kinds Herdmanella Darboux. ff. Median antenna inserted ventrally. Notopodial setae of two kinds, all finer than the neuropodials Gastroceratella Darboux. dd. Dorsum normally left in part uncovered by the elytra. Median antenna inserted at the margin; notopodial setae coarser than the ventrals. e. Notopodial setae with transverse series of spinules Lagisca Malmgren. ee. Notopodial setae simply serrate or wholly smooth. /. Notopodials smooth; tip of ventrals simple Hermadion Kinberg. //. Notopodials serrate; tip of ventrals bifid Scalisetosm Mcintosh. 40 THE ANNELIDA POLYCHAETA. Synonymy of Genera. Nychia Malmgren being preoccupied is replaced by Gattyana Mcintosh. Evarne Malmgren is also preoccupied (Adams, Moll., 1858) and is here replaced by Evarnella, nom. nov. Bylgia Theel is preoccupied (Miinst., Crust.) and is replaced by Bylgides, nom. nov. Langerhansia Mcintosh is preoccupied by Langerhansia Czerniawsky, a syUid genus. Eupolynoe seems first to have been used by Mcintosh without diagnosis or discussion. He at that time placed under it (Ann. mag. nat. hist., 1874, ser. 4, 13, p. 264) two new species, occiden- talis and anticostiensis. The first seems to conform to Eucranta Malmgren and is quite likely E. villosa Malmgren, type of the genus; anticostiensis is appar- ently a Harmothoe. Accordingly Eupolynoe is suppressed. Hololepidella Willey (Ceylon pearl oyster fisheries report 1905, pt. 4, p. 251) seems identical with Lepidametria Webster. Adyte St. Joseph is regarded as a synonym of Scalisetosus Mcintosh. Parapolynoe Czerniawsky does not seem sufficiently different from Polynoe to make separation justifiable. Norepea Johnston (1865) falls as a synonym to IpMone Kinberg. It was established with Polynoe peronea Schmarda as the type, but that species is the same as Iphione muricata (Savigny). Plotolepis, gen. nov.^ Body short and slender, with the somites comparatively few. Eyes four, small, sessile, the anterior pair more widely separated and those on each side close together. Prostomium bearing anteriorly a median and two lateral tentacles. Parapodia lacking notopodial lobe and notopodial setae. Neuropodia elongate, with setae numerous. Setae in two groups, a smaller ventral one of coarser hairs and a dorsal one of much more numerous finer hairs. Heads of setae scaled, tips entire. Notocirri of two types, most of them being conspicu- ously elongate, all in the anterior region and in the posterior region those of alternate pairs, the intermediate ones of normal character. In the type the elongate cirri are gi-eatly inflated and apparently act as floats. The elytra are borne on somites II, IV, V, VII, IX, XI, XIII, XV, XVII, XIX, and XXI. They are very small, with elytrophores large; not at all extend- ing over dorsum, each reaching but httle beyond its elytrophore. All but the most posterior ones inflated, vesicular. ' 7rXco7ds, floating, and Xe?ris, scale. PLOTOLEPIS NANS. 41 Genotype. — P. nans, sp. nov. This genus is characterized especially by the remarkable modification of a definite number of the notocirri into the elongate and more or less inflated organs above described and also by the vesicular character and greatly reduced size of the anterior elytra. These modifications clearly suggest adaptations to the pelagic habit which is relatively uncommon in the family. Moore's Drieschia pellucida (Proc. Acad. nat. sci. Phila., 1903, p. 794, pi. 50, f. 1-12), taken in the Atlantic off Woods Hole, is clearly also a member of this genus, presenting the same inequaUty in the notocirri, the vesicular elytra, and similar form and general proportions of the setae. Plotolepis nans, sp. nov.^ Plate 7, fig. 3, 4. The body and its appendages in general are colorless or but sHghtly tinged with brown, apparently from preservation, and are transparent or translucent. The eyes are black and the setae are colorless and transparent. The body is very short. It is widest in the anterior half where the diame- ter does not vary much ; but from near the middle caudad it narrows uniformly and conspicuously. The tj^e is but 6.4 mm. in length. The greatest width over all, that is from tip to tip of opposite setae, is 7 mm., thus exceeding the length ; and the mdth across the body alone is but 1 mm. The total of somites in the type is only twenty-one. The number of pairs of elytra is eleven. The prostomium is about three fourths as long as wide. On each side it is evenly convex or weakly angular at the middle. Anteriorly it presents an excision in which the cirratophore of the median tentacle fits. On each side of this the horn of the prostomium bears the lateral tentacle. It is convex above and has the usual mecUan longitudinal furrow, wliich is narrow and weak mesally but mdens anteriorly where it passes into the anterior incision and posteriorly where a narrow triangular tongue extends into it from the second somite. The four eyes are small as usual, with the anterior a httle the larger. The anterior eyes are much more widely separated than the posterior, and are situated on the sides of the head, the posteriors being more dorsal and each facing ectocaudad. The two eyes on each side are separated by less than their ' nans, a swimmer. 42 THE ANNELIDA POLYCHAETA. diameter. The ceratophore of the median tentacle is longer and much thicker than those of the laterals and narrows moderately distad; the style is long and slenderly uniformly tapered, reaching to the sixth somite. The ceratophore of each lateral tentacle is contiguous proximally with that of the median, narrows distad so as to have the form of the frustum of a cone, and projects cephalo- ectad; the style is clearly less than half as long as the median and reaches only to the second somite. The palpi are long and cyhndrical, narrowing gradu- ally toward the end and then more abruptly into a much more slender tip. They greatly exceed the lateral tentacles in length. (Plate 7, fig. 3). The tentacular cirri, that is, the cirri of the peristomial parapodia, are attached at a level a little caudad of the middle of the prostomium. The dorsals and ventrals are equal in length, which much exceeds that of the median ten- tacle, reaching to the eighth or ninth somite. The metastomial somites are strongly convex above, more flattened ven- trally. The first above is produced forward at the middle into a triangular tongue extending over the caudal border of the prostomium and fitting in the middorsal furrow of the latter. These somites increase in length to the fifth or sixth in which the length is equal to that of the prostomium and the width about two and a third times the length. In the seventh or eighth soinite from the caudal end the width is scarcely or not at all more than one and a half times the length, which remains actually about as in the somites of the middle region. There are no sharply defined intersegmental furrows. The anal cirri are missing. The parapodia are long and relatively slender, excepting those of peri- stomium and first metastomial somite much exceeding the width of the somites to which attached. Each parapodium is widest a little distad of the base from where in outline as viewed from above it is at first of uniform width and then from near the middle narrows to the distal end at wliich it is compressed to an edge. Just proximad of the distal end it is raised into a thin ridge or plate both above and below so that the outline as viewed from in front or behind increases in height distad of the middle, again descending to the somewhat pointed distal end. At the distal end it is produced into a subtriangular, dis- tally somewhat rounded, presetal process or lip. There is no distinct post- setal lip. There is no distinctly indicated notopodial lobe and there are no notopodial setae. The notocirri are attached at the extreme bases of the para- podia above. Their cirrophores are typically remarkably inflated above the pedicel-hke bases into subcylindrical bladder-like cushions or vesicles which in the middle region of the body greatly exceed the adjacent elytrophores in PLOTOLEPIS NANS. 43 size; the cirrophores of the first pak of notocirri are smaller than those of the immediately succeeding pairs, while those of the caudal region are in part more markedly reduced, with correspondingly shortened styles, the most posterior ones being smaller than the adjacent elytrophores. The styles of the longer type of notocirri are for the most part remarkably long, those of the first pair, e.g., when laid back caudad, reaching to the twelfth somite, being decidedly stouter and much longer than the tentacular cirri and in the type having an actual length of 3.5 mm. The styles of the second and third pairs of notockri are missing in all the types, but the cirrophores of these pairs are decidedly larger than those of the first pair, those of the third being largest of all, and the size of the basal scars would incUcate that the styles were of proportionate length. The cirrophores of the fourth pair are again reduced but are larger than those of the first pau-; in one paratype in which the style on one side is still present, the latter is seen to exceed in actual length that of the first pair, and when laid back, to extend over the eight succeeding somites, reaching thus from its own somite (the tenth) to the nineteenth. The fifth pair of notocirri are abruptly very different from the preceding ones, having an ordinary non-inflated cirro- phore smaller than adjacent elytrophores and bearing a style of ordinary form and size, this extending only to or scarcely beyond the middle of the parapodium. The next notocirri, the sixth, are again of the inflated type, with styles a Uttle shorter than those of the fourth pair, the seventh are again of the reduced type, the eighth again long, and so on. Thus there are the very elongate special notocirri on somites III, VI, VIII, X, XIV, and XVIII (in the type that of the eighteenth is relatively short though long in the paratype) ; short ordinary notocirri on somites XII, XVI, and probably XX. The neurocirri of the first metastomial pair of parapodia are attached at the extreme base of the latter; they are long and tapered, extending cUstad beyond the tips of the setae of the parapodium. All succeeding nem-ocirri attached a little proximad of the middle of parapodium, and short, failing much of attaining the end of the parapodium, in those of the middle region by as much as or more than their own length. Elytra are borne on somites II, IV, V, VII, IX, XI, XIII, XV, XVII, XIX, and apparently also in a much reduced condition on XXI. The elytrophores in general are stout and cylindrical and extend dorsoectad from the bases of the parapodium. Most elytra are missing, but a few remain in one paratype. These are all small, having in general a maximum diameter only about twice that of the elytrophore. In outUne each is broadly ear-shaped or suborbicular with an indentation on the exterior side and toward the anterior end. They are 44 THE ANNELIDA POLYCHAETA. inflated and vesicular, upper and lower surfaces being decidedly convex, and are essentially smooth. The elytra of the nineteenth somite are smaller, each capping the long elytrophore and extending but little beyond it on each side; it is more nearly orbicular, lacking the indentation on the outer side. The neuropodial setae are arranged in a vertical plane in which they spread out in a fan-hke manner. They are of two distinct types in a dorsal and ventral group respectively. The ventral group consists in most cases of two setae but often of three and sometimes of up to four or five in the middle region of the .body, wluch are shorter and stouter than the others with the heads short and not finely extended at the tip. The setae of the dorsal group are much longer and more slender throughout and much more numerous, the number being ordinarily from twelve to eighteen in parapodia of the middle region of the body, becoming fewer in the anterior region. In the ventral type the head is in out- line somewhat like that of the head of a spear with one side slightly concave, the other shghtly convex, with the tip bent a httle toward one side; seriate finely pectinate scales occur along the concave side from base to tip of the head in two partly interlocking series; there is no subapical tooth. (Plate 7, fig. 4). In the setae of the dorsal group the heads are more slender and much more elongate, being drawn out distally above the series of scales into a long, very fine, smooth tip which is commonly more or less curved. In the first metas- tomial parapodia of the type only setae of the first, stout type are present, there being five of these in each; in a paratype a seta of somewhat intermediate form appears. No setae were detected on the peristomial parapodium. Locality. Easter Island: 29 miles northeast of North Cape. Sta. 4694, (lat. 26° 34' S., long. 108° 57' 30" W.). Surface. 22 December, 1904. Four specimens. It is possible that the type-specimens of tliis species are not wholly grown; but they are so strongly characterized that there is no likelihood of difficulty of recognition. The most salient features of the form are those manifestly adap- tive to its pelagic Ufe, such as the long parapodia and setae, the inflated though small elytra, and particularly the greatly elongate, apparently pneumatic notocirri. As judged by the much inflated and large cirrophores, the style of the notocirri on the sixth somite, missing in the types, must have been of most 6 xceptional length. PODARMUS. 45 , 1 PoDARMXJS, gen. nov. Body short, tapering caudad, composed of comparatively few somites. Colorless and transparent. Prostomium wider than long, divided by a median furrow. Bearing three tentacles all of which are inserted marginally. Ceratophore distinct, the style smooth and tapering. Palpi long and slender, gradually acuminate. Parapodia uniramous, long (typically exceeding in length the width of the somite), at the distal end compressed anterocaudally and divided by a vertical fissure into a presetal Up and a shorter postsetal lip. Notocirrus attached toward base of parapodium above, long. Neurocirri attached distad of middle, short and subulate. A conspicuous cylindrical process extends from the caudal face near the same level as the neurocirrus than which it is much stouter but shorter. Only neuropodial setae present, these consisting of stouter ventral ones and but Uttle more elongate though much more slender dorsal ones, the head in these being very much more drawn out. The two forms equal in number or nearly so. Tips entire. No special natatory setae. Character of elytra not known. Elytrophores in type fourteen pairs, occurring on somites II, IV, V, VII and alternate somites to XXIII inclusive and then on XXVI and XXIX. Genotype. — P. ploa, sp. nov. Apparently this form is mostly closely related to Drieschia Michaelsen, but it differs in possessing the characteristic posterior process on the parapodia and conspicuously in the form and proportions of the setae. In the present form the two types of setae are obviously a modification of the same primary type, and the coarser ventrals are nearly as long as the dorsals and are numerous, being essentially equal in nmnber to the dorsals with which they are not inter- mingled. In Drieschia pelagica Michaelsen, type of that genus, as indicated by Michaelsen' s description and figures, the stout setae are proportionately to the dorsals very much shorter, more or less strongly curving sigmoidally, and very much fewer than the fine dorsals, which in turn proportionately to the parapodia are very much longer. ' -irovs, foot, and ap/ids, a peg, in reference to the cylindrical process borne on the posterior side of the parapodium. 46 . THE ANNELIDA POLYCHAETA. PODARMXJS PLOA, Sp. nOV.^ Plate 6, fig. 6; Plate 7, fig. f. 1, 2. Color indeterminable from types because of their darkening in the fixing fluid. Probably colorless and transparent like most other pelagic species of annelids. Body comparatively short. Widest toward anterior end, the anterior end narrowing a little and the body narrowing very gradually and continuously caudad. Length of type nearly 9 mm.; width over all, that is to end of setae, about 4.2 mm. Total number of segments thirty. Number of pairs of ely- trophores fourteen. The prostomium is wider than long. It bulges out on each side but the outline laterally is rather evenly convex, not at all angular. The prostomium is divided symmetrically as usual by a deep median longitudinal furrow. Each half is subquadrate, not at all somewhat diamond-shaped as in Harmopsides. The ceratophores of the tentacles are cylindrical and extend directly forward. That of the median tentacle is stouter and longer in a paratype, but differing slightly in the type. The styles of the tentacles are broken off excepting one lateral one in a paratype. This is slender and terete, distally narrowing gradu- ally to an acute point, not abruptly reduced to a filament. It is considerably shorter than the palpus. The palpi are slender and gradually acuminate, not abruptly reduced distally. The parapodia of the peristomium occupy the usual position. The distal . ends of the ceratophores are nearly on a level with the anterior end of the pro- stomium. The dorsal cirrus is gradually attenuate tliroughout its length. It exceeds the palpus in length. Ventral cirri missing. Dorsal surface of metastomial segments convex, the ventral more flat- tened as usual. Neural ridge evident, rather narrow, set off by shallow fur- rows. No anal cirri. Parapodia in the types as preserved relatively long, exceeding in length the width of the segments to which attached. Subconically enlarged at base in the usual way; distad of elytrophores and dorsal cirri slender and nearly cylindrical, but a little less in diameter at middle than more distad. The end region of each parapodium is flattened in the anteroposterior direction and in dorsal view appears narrowed distad; the end is divided by a subvertical fissure sepa- ' TrXojds, floating. PODARMUS PLOA. 47 rating a presetal lip from a little less shorter postsetal lip. Between the apical Ups the setae are inserted in vertical series and spread out in a conspicuously fan-hke form. The notopodial lobe is represented by a low, rounded elevation and bears no setae. Each dorsal cirrus is attached toward the base as usual; the cirrophore is swollen, narrowed distad; the style is proximally rather stout, evenly attenuated distad and reaching to near the tips of the longest setae and in life probably exceeding them. The ventral cirrus attached distad of the middle of parapodium ; short and subulate, not fully reaching end of neuropodium. Elytra all missing. Elytrophores cylindrical, of moderate length, fourteen pairs inserted on the following somites: II, IV, V, VII and alternate segments to the twenty tliii'd and then on XXVI and XXIX. The neuropodial setae are arranged in a vertical plane in which they spread out more or less in fan-like manner. They are of two distinct types: a ventral group of which the members are shorter and stouter, both proportionately and actually, with the heads shorter and less slender at tip; and a dorsal group of longer and more slender setae in which the heads are elongate and apically slenderly drawn out. In setae of the ventral group the head is spear-shaped in outline with the sides above the fusiform basal thickening first concave and then nearly straight, till at the tip one side is convex and the other concave, the acute tip bending over toward one side; on this side from base of head to tip are two series of a few well-separated scales; no subapical tooth. (Plate 7, fig. 1, 2). In the dorsal group the heads of the setae are much more narrow and elongate, with above the series of scales a very long and slender essentially smooth tip which is flexible and appears ordinarily more or less curved dorsad. (Plate 6, fig. 6) . The two kinds of setae are typically about equal in nimaber, there being fifteen of each, or a total of thirty in the parapodium of the type. The setae of the first metastomial parapodia are shorter, with the heads less elongate, the setae of the ventral type predominating. The acicula are small and neither pro- trudes from the surface. Locality. Off North Cape: Easter Island. Sta. 4694 (lat. 26° 34' S., long. 108° 57' 30" W.). Surface. 22 December, 1904. Three specimens. The specimens were fixed in Fleming's fluid. They are of varying sizes, and proba- bly even the largest is not fully grown. This form has a similar general appearance to Harmopsides nans, a simi- larly pelagic form. Both have similar comparatively short bodies with the number of elytra correspondingly reduced. The present species in life was doubtless transparent. The fixing of the types m Fleming's fluid, however, blackened the tissues. 48 THE ANNELIDA POLYCHAETA. Harmopsides, gen. nov.-' Body short, composed of comparatively few somites, colorless and trans- parent. Prostomium -nider than long, divided into two equal halves by a deep median furrow, each half in outline somewhat diamond-shaped. Tentacles three, inserted marginally. Ceratophores distinct and the styles smooth and subulate. Palpi comparatively long and slender, pointed. Parapodia long, with the notopodium represented only by a slight non- setigerous tubercle into which the tip of an aciculum extends. At the end of the neuropodium a digitiform presetal process into which the aciculum penetrates. Notocirri long. Neurocirri attached well distad of the middle of the parapodium, all small excepting the first which is attached near the base of the parapodium and in length is comparable to a tentacular cutus. Setae of two forms, both a modification of the same fundamental type, the first consisting of stouter ventrals with short heads and the second of much more numerous and greatly elongate finer ones of the dorsal portion of fascicle in which the heads are slenderly elongate. Apices of aU setae bifid or with a subapical tooth. Elytra not known. Eighteen pairs of elytrophores in the type-species, these occurring on somites II, IV, V, VII, IX, and then on alternate ones to the XXIII and thereafter on XXVI, XXIX, XXXII, XXXIV, XXXVII, and XL. Armature of the proboscis as usual in the family. Genotype. — H. natans, sp. nov. This genus is near Nectochaeta Marenzeller, erected for grimaldi Marenzeller, taken in the Atlantic. It is regarded as distinct especially because of the presence of the prominent subtentacular process, the absence of all notopodial setae, and the larger number of soinites, the elytra numbering eighteen pairs as against only eleven in Nectochaeta. Harmopsides natans, sp. nov. Plate 6, fig. 1-5. The body of the type as preserved having a very dilute yellow tinge but probably colorless in life, as are the paratypes at present, transparent. ' apuds, a peg, and Hn^j face, in reference to the subtentacular process. HARMOPSIDES NATANS. 49 Body short. It is widest near the sixth somite from where it tapers con- tinuously to the caudal end. The greatest width inclusive of the parapodia is attained a Uttle farther caudad, since the anterior parapodia are shorter than the succeeding ones, those toward the caudal end also decreasing in length. Dorsum convex, the venter less so and with a distinct neural ridge set off on each side by a sharply impressed narrow fiurow or sulcus. Length, 17 mm.; greatest width, exclusive of parapodia, 2 mm. ; width to tips of parapodia, 5.2 mm.; and to tips of setae nearly, 9.5 mm. Number of somites forty-four; number of pairs of elytra, eighteen. The prostomium is wider than long. On each side it protrudes strongly and angularly, the apex of the angle being at the middle of the length. It is separated into two equal halves by a deep median longitudinal furrow. Each half or lobe is prolonged dii-ectly forward into a terete and slightly clavate ceratophore which is somewhat constricted at the proximal end. Each eye of the anterior pair is located on the protruding lateral angle of the corresponding lobe. The eyes of the posterior pair are smaller in size, much closer together, and dorsal in position. Each is separated by about twice its diameter from the corresponding anterior one. The ceratophore of the median tentacle is inserted anteriorly between the two halves of the prostomium. It is cylindrical, some- what narrowed distad, and equal in length to the lateral ones. Proximally the style is of the same thickness as the ceratophore but tapers continuously and uniformly for about two thirds of its length and then more rapidly into a slender, filiform, and acutely pointed tip. Its total length, inclusive of ceratophore, is about four times the length of the prostomium proper. The styles of the lateral tentacles are of the same form as that of the median but are more slender and shorter. The palpi are comparatively slender. Each narrows from its base continuously to a slender acute tip, and in length is equal to the median tentacle or nearly so. (Plate 6, fig. 1). The peristomium shows distinctly above as a transverse band which is small, with its anterior margin convex. The parapodia extend obliquely for- wards, the distal ends of their cirrophores attaining the level of the anterior margin of the prostomium. Each bears a stout spine or aciculum and three small, curved, somewhat sickle-shaped, setae. Each cirrus tapers gradually to a slender tip, the upper one extending distad the same distance as the palpi while the inferior one is shorter. The parapodia are relatively long and, except in the anterior region, equal or surpass the width of the somite to which attached. Proximad of the elytro- 50 THE ANNELIDA POLYCHAETA. phores and dorsal cirrophores the parapodia are thicker anteroposteriorly and deeper, the dorsal hne rising dorsomesad while the ventral one remains hori- zontal ; distad of this they continue to narrow to the slight notopodial eminence, beyond which the nenropodium is very slender and more uniform in thickness. The neuropodium at the distal end is produced into a slender digitiform process through one side of the base of which the aciculum protrudes. The notopodium is a slight tubercle on the dorsal surface into which an aciculum extends but which bears no setae. The ventral cirrus is attached distad of the middle of the parapodium and is a small, slenderly subulate filament not attaining the end of the neuropodium. The dorsal cirri are found on the parapodia of the somites between those bearing elytra. In each of these beyond the swollen basal joint, or cirrophore the style continues as a gradually and slenderly acuminate fila- ment which reaches to or extends a little beyond the distal ends of the longest setae. The acicula are cUstally a little denser or less clearly transparent than proximally. The notopodial one is shorter and more slender than the neuro- podial. Only neuropodial setae are present. These are of two types. On the ventral side of the setigerous surface of the nem"opodium is a group of stout setae of ordinary length each of which ends in an asymmetrical, lanceolate head. (Plate 6, fig. 5) . A little below the apex of the head is a small subapical tooth and proximad of this, over the entire length of the more obUque side, is a close series of ovate, lanceolate scales. Above this ventral group are setae of a sec- ond type which are three or more times as numerous. These are of smaller ac- tual diameter and at the same time much longer, the longest being from two to three times the length of the ventrals. They are comparable in structure to ventral ones imagined as greatly stretched, giving an exceedingly long and slender and usually gently curved head along the convex side of which the scales are correspondingly more widely separated. (Plate 6, fig. 3, 4) . In each there is a small subapical tooth which seems to be easily lost. Some setae show the scales along two sides, but the scales on one of the sides form only a short series. The elytra are aU missing. Eighteen pairs of elytrophores are distinguish- able in the type. The elytrophores are subcylindrical and of moderate length, decreasing in diameter and length caudad. The bases of the parapodia between those bearing the elytrophores are somewhat more crassate than the others. The elytrophores occur on somites II, IV, V, VII, IX, and on alternate suc- ceeding somites to XXIII, and then on XXVI, XXIX, XXXII, XXXIV, XXXVII, and XL. HARMOTHOE HIRSUTA. 51 The two anal papillae are short, somewhat swollen at base, and slender distally. In a paratype from Sta. 4675, near 10 mm. long, the extended proboscis is 1.8 mm. long with its greatest diameter scarcely less. Along the distal edge there are nine ventral papillae and nine dorsal ones, these flattened and lanceolate or ovate-lanceolate in outline. (Plate 6, fig. 2). Localities. Off the coast of Peru. Sta. 4668 (lat. 12° 9' S., long. 81° 45' W.). Surface. 19 November, 1904. One specimen (type). Off Peru. Sta. 4661 (lat. 10° 10' S., long. 82° 02' W.). 300 fms. to surface. 15 November, 1904. Four specimens. Off Palominos Light House: Peru. Sta. 4675 (lat. 12° 54' S., long. 78° 33' W.). 300 fms. to surface. 22 November, 1904. Two specimens. Off southwest coast of Central America. Sta. 4613 (lat. 9° 43' N., long. 86° 15' W.). Surface. Surface temp., 82-79° F. 19 October, 1904. Two specimens. Off Peru. Sta. 4663 (lat. 11° 20' S., long, 88° 55' W.). Surface. Surface temp., 69° F. 15 November, 1904. Two specimens. Off Peru. Sta. 4664 (11° 30' S., long, 87° 19' W.). Surface. Surface temp., 68° F. 17 November, 1904. One specunen. Off Peru. Sta. 4669 (lat. 12° 13' S., long. 80° 24' W.). Surface. Surface temp., 67° F. 19 November, 1904. Six specimens. Between Peru and Easter Island. Sta. 4676 (lat. 14° 29' S., long. 81° 24' W.). Surface. 5 December, 1904. Two specimens. Harmothoe Kinberg. Ofvers. K. vet. akad. Forh., 186.5, no. 4, p. 386; McIntosh, British annelids, 1900, 1, pt. 2, p. 313; Darboux, Bull. sci. France & Belgique, 1900, 30, p. 106 (in part). Eumolphe Oken, Lehrb. naturgesch., 1815, 1, p. 375 (in part) ; Blainville, Diet. sci. nat., 1828, 57, p. 457. Eupolynoe McInto.sh, Ann. mag. nat. hist., 1874, ser. 4, 10, p. 13 (in part). Harmothoe hirsuta Johnson. Plate 2, fig. 2-8; Plate 3, fig. 1. Proc. Cal. acad. sci. Zool., 1897, ser. 3, 1, p. 182; Ehlers,'Zoo1. jahrb. Suppl., 1901, 2, p. 253; Abhandl. K. gesellsch. wiss. Gottingen. Math. phys. klasse, 1901, p. 42. Two apparently immature specimens from islands off Panama are referred to this species which occurs from the California coast at San Pedro southward 52 THE ANNELIDA POLYCHAETA. to the Chilean coast. In general structure they agree with adults of hirsuta from San Pedro excepting that the notopodial setae are comparatively more slender, being mostly clearly more slender than the neuropodials and more numerous than is typical, and that the anterior eyes are rather more dorsal in position and thus clearly visible in dorsal view. Above they show the char- acteristic nuchal process from the anterior edge of the first metastomial somite which, as pointed out by Ehlers, serves as an easy distinguishing mark in com- parison with the closely related Harmothoe -polytricha (Schmarda) which occurs on the other side of the isthmus in the Caribbean region. The parapodia of the peristomial somite bear three (or sometimes two) conspicuous setae. The small specimens from Panama are described in full below. The body is short. It is widest near the junction of the first and second fourths of the length but narrows only weakly from there caudad to the begin- ning of the last fom'th over which it narrows more strongly to the pointed anal end; anteriorly also narrows strongly to the prostomium. The dorsum is only shghtly arched. Venter also shghtly arched, and presenting a sharply limited, caudally tapering, ridge. Total length of one specimen near 11 mm.; greatest width, exclusive of parapodia, 2 mm.; width to ends of parapodia, 3.5 mm.; width to ends of setae, 5.6 mm. Number of somites thirty-seven. Prostomium decidedly wider than long, sloping strongly from behind forwards. A wide median longitudinal furrow dividing it into two symmetrical halves. Each half rises to a longitucUnal ridge extending forwards to the apex of the peak, the prostomium otherwise smoothly rounded. On each side it bulges convexly into an optical lobe. Each anterior eye situated rather laterally on the lobe and distinctly visible from above. The posterior eyes are much closer together and are dorsal in position; they are more than three fourths the diameter of the anterior ones, from which they are separated by three times their diameter or nearly so. The peaks are conspicuous; each is a stout sub- conical process extending over the base of the corresponding lateral tentacle, its abruptly narrower tip separated by a wide space from the median ceratophore, though this space is less than the half-diameter of the ceratophore at its base. The peaks in one specimen are darkened. The ceratophore of the median tenta- cle is stout and much narrowed distad; it is blackish in color, contrasting strongly with the prostomium; the style is missing. The lateral tentacles arise from beneath the base of the median ceratophore. Each lateral ceratophore is cylindrical, shorter and much less thick than the median. In one specimen the style is nearly twice the length of the prostomium and in the other specimens is HARMOTHOE HIRSUTA. 53 considerably shorter than this; it is dusky in color; it is terete, a little narrowing to near the middle of the length and then more quickly narrowing into the slender terminal filament. The palpi in length surpass the lateral tentacles. They are stout proximally, narrow strongly distad and toward the end are more abruptly reduced and end in a paler, slenderly conical tip. Dusky in color. (Plate 2, fig. 2). The parapodia of the peristomium lie close at the side of and partly beneath the prostomium. Each bears three curved setae of the notopodial type. The metastomial somites are all distinctly separated. Excepting toward the end of the body they are of nearly uniform length which is mediuin. The first three somites on the ventral side are bent caudad at the middle into a short subrectangular flap or tongue-like process. NephricUal papillae low, rounded. Parapodia prominent but shorter than the width of the somites. A typical parapodium at the proximal end is very deep but is compressed anterocaudally. The neuropodium is a short subcylindrical process extending obhquely dorso- ectad from near the middle of the dorsal surface of the parapodium; distally it is truncate, the distal surface bearing the numerous setae, and the ventral edge is extended into a slender, subulate acicular process. The neurocirrus is attached on the ventral surface proximad of the middle; the cirrophore is short and narrows distad to the base of the style which at its beginning is of the same width; the style is short and subulate, reaching the bases of the nearest neuro- podial setae but fails much of reaching the end of the neuropodimn; the cirro- phore is dark but the style pale. The notocirri are stout and subcorneal, usually darkened or dusky; they are densely clothed vfith long ciUa mostly exceeding in length the diameter of the style. (Plate 2, fig. 3). The acicula are pale, extending into the acicular processes but not pro- jecting beyond the neuropodial, and but little beyond the notopodial, process. Neuropodial aciculum much stouter than the notopodial. Nem'opodial setae much exceeding the notopodials in length; arranged in vertical series spreading in fan-like manner ; about forty in number in the parapodia of the median region. Each consists of a slender shaft and a spear-like head, the seta gently curved from a little below the head to the tip. Head bidentate, the principal tooth a little curved, the subapical tooth small, straight, and acute, parallel, or nearly so, to the axis of the principal tooth ; convex side of the head densely pectinate from the base nearly to the lower tooth. The most ventral neuropodials are shorter than the others, wth the heads much reduced in length. (Plate 2, fig. 7, 8 ) . The notopodial setae are very numerous and are densely arranged in whorls; 54 THE ANNELIDA POLYCHAETA. the outer setae on the proximal side are much shorter than those in the inner part of the fascicle and on the distal side. Each notopodial is slender and gently curved; the smooth apex is short and acute with no trace of a subapical tooth; the conspicuous pectinae extend from the tip over nearly the whole length of the exposed portion of the seta, the smooth proximal portion of the shaft being short. (Plate 2, fig. 4-6 ; Plate 3, fig. 1). The elytra are all missing in the specimens studied. The elytrophores have the usual arrangement, occurring on somites 2, 4, 5, 7, etc. They are short and proportionately thick and present the usual subelliptic to ear-shaped scars. The body is greyish, in part of a dusky tinge ; a darker area on each somite at each lateral end on the ventral surface and a dark ring about the proximal end of each neiu"ocirrus. The notopodial setae are orange in appearance. The neuropodials are paler, dilute yellow. Locality. Panama: Perico Island. Shore. 26 October, 1904. One specimen. Panama: Taboguilla Island. Shore. 30 October, 1904. One speci- men. Harmothoe mexicana, sp. nov. Plate 1, fig. 1-9; Plate 2, fig. 1. The body is well pigmented, being in general a rather dark brown with the parapocUa a shade hghter. There is typically a paler narrow median longi- tudinal stripe along the venter. The palpi and the other appendages of pro- stomimn and peristomium are yellowish to whitish as are also the cirri. Seg- mental papillae whitish. Setae yellowish. The body narrows strongly cephalad from the fifth or sixth somite, the anterior end appearing convexly rounded laterally as well as anteriorly. From the fifth or sixth somite, the region of greatest width, the body proper narrows continuously caudad and at the caudal end is very narrow; however, the para- podia, with their setae, increase in length from the anterior end toward the middle, so that the decrease in width of the body proper is offset for a considerable distance. In the region of the greatest width the depth is about the same as the mdth exclusive of the parapodia; the depth is less cephalad of this level and decreases caudad from it in such manner that the caudal region may appear conspicuously flattened. A specimen 39 mm. long has a maximum width to the HAKMOTHOE MEXKWNA. 55 bases of the parapodia of 3.8 nim. ; widths to tips of parapodia, 6 mm. ; and to tips of the setae, 8.2 mm. The prostomium in front presents two very large, conical peaks which pro- ject forwards, one on each side of the median ceratophore. These peaks vary considerably in the amount of their projection. There is a black area at the base and caudad of each. CaudaUy the prostomium is rounded, expanding from the caudal end to the middle and thus convexly bulging on each side. There is a well-marked median longitudinal furrow from the base of the median ceratophore caudad, and also a transverse furrow, caudad of which the pro- stomium is typically more elevated. Two pairs of eyes of which the caudal ones are dorsal and are much closer together than the anterior ones, which are low on the sides or subventral and not typically evident in dorsal view. Each lateral tentacle projects from beneath the peak of the corresponding side. Each lateral ceratophore is attached beneath the base of the peak and projects ventrad and is short and cyhdiic. The lateral tentacles are about as long as the pro- stomium inclusive of its peaks. Each tapers uniformly from its base to the very slender and acutely pointed tip. The ceratophore of the median tentacle is a stout cyUndrical body which narrows more or less distad; its distal end is nearly on a level with that of the peaks. The palpi are about twice the length of the prostomium. Each is terete and narrows uniformly distad to an acute tip. There is no distinct terminal filament. (Plate 1, fig. 1). The parapocUa of the peristomium have the usual position. The cerato- phores attain or a little surpass the level of the most caudal point of the median tentacular ceratophore but fall much short of attaining the level of the apices of the prostomial peaks. The tentacular cirri taper evenly from base to the slender tip and considerably exceed the palpi in length. Each parapodimn bears two, or sometunes three, stout setae resembling the notopodial setae of the succeeding somites, each thickest proximally and narrowing distad to the acute apex. (Plate 1, fig. 1). The metastomial somites are moderately arched above and below, the ventral convexity sometimes appearing considerably more arched than the dorsal. Ventrally there is a wide median fm-row, most of which is occupied by the neural ridge. Pygidium a small and almost tubercle-like projection. Anus terminal. Neplu'idial papillae begin on the sixth somite as usual. They are minute, short, subcyhndi-ic processes of whitish color projecting from a small tubercle at the base of the parapodimn. Each extends straight ectocaudodorsad, or the somewhat longer ones of the middle region curving more dorsad distally. 56 THE ANNELIDA POLYCHAETA. The parapodia are short, being considerably shorter than the width of the somite to which they are attached, excepting in the narrower caudal region. They appear flattened in the cephalocaudal direction. Depth proximally great and equalling or exceeding the length exclusive of the setae. Narrowing moderately distad, the dorsal edge being nearly horizontal and the ventral oblique. The two rami are distinct and well separated, the neuropodium a httle exceeding the notopodium. Each branch is conically narrowed and drawn out distally into a slender acicular process. The neurocirri are very small, short and subulate. Each is attached at the middle of the ventral surface and reaches to the distal end of the neuropodium proper or a little beyond it, but not to the end of the acicular process excepting in the second parapodia. The neurocirri of the second somite are much longer, extending beyond the ends of the setae. The notocirri are slender and filiform, distally subulate. They extend out well beyond the tips of the setae. Their cirrophores are attached close to the bases of the notopodia and are large and conical. (Plate 1, fig. 2). In each branch of the parapodium there is a single aciculum which is pale yellow in color and is plainly transversely striate. The tip of the neuropodial aciculum projects freely at the side of the tip of the acicular process, which exceeds the aciculum. The notopodial aciculum extends through the acicular process and exceeds the neuropodial. The notopodial setae are in a spreading whorl, diverging distad and bending mesad conspicuously over the dorsum, especially in the caudal region, much as in yokahamiensis. They are pale yellow in color. Each is typically a blade-like structure widest at its middle, narrowing moderately proximad and distally narrowing to an acute point. One side is more nearly straight than the other and is commonly a little concave or angu- larly inbent, the other edge being convex. One of the broad surfaces is com- monly concave and the other convex, or the seta in cross-section at the widest part may be subtriangular. On the convex side there are numerous cross-series of spines or pectinae, the number being commonly about fifty; a rather long distal region or tip is free from pectinae. At the widest part the full-sized noto- podial setae have twice, or slightly more, the maximum diameter of the ventrals. The most dorsal are longest and have a length (free portion) as great as the length of the corresponding neuropodials or nearly so. (Plate 1, fig. 9). The neuropodial setae are long and fine, and present a long smooth shaft, a pecti- nate distal division, and a smooth, acute, bifurcate tip as usual. They are not of the same structure throughout the fascia, in each of which there may be from thirty-six to forty or more setae. The more dorsal and more nimierous HARMOTHOE MEXICANA. 57 setae are widest at the proximal end of the pectinate division from where they narrow distad to the slender acute tip; each bears ordinarily thirty-five to forty pectinae ; the smooth tip ends in a slender principal tooth or prong which is nearly straight along its mesal edge and convex on the ectal; the accessory subapical tooth is very short, straight and divergent, and varies considerably in proportionate length and stoutness. In a second type of neuropodial the general form is similar to the preceding but the pectinae are much lower, more like those of the notopodials. The setae of the most ventral series are conspicu- ously different. The yare much shorter and more slender and each distally, beginning at the proximal end of the pectinate division, is strongly curved. Each ends in a slenderly acute and entire tip. (Plate 1, fig. 5-8; Plate 2, fig. 1). The peristomial setae are of the general tj^De of the notopodials. The elytra are of the usual number and arrangement. They are moderate in size. In outline they are subrotund, but with the anterior and ectal edges more or less flattened and nearly straight, so that the outline sometimes appears subtriangular with the hypotenuse more convex. Each is densely studded with conical, corneous, and colorless papillae each of which rises from a more expanded, darker, disc-Uke base. These project from the caudal and ectal edges. No soft papUlae proper were detected. CiUa occur sparsely over the entire surface, these projecting sparsely between the papillae of the general surface as well as between the marginal ones of the caudal and ectal edges. The cilia are slenderly cylindiical or distally sUghtly narrowed, transparent, and of moderate length. The elytrophores are of moderate size. Each presents the usual ear-shaped scar. In position corresponding to that of the elytrophores, there is on each non-elytrophorous somite on each side a conspicuous, stout, conical and light colored process. Localities. Off Mexico. Sta. 3425 (lat. 21° 19' N., long., 106° 24' W.). Depth, 680 fms. Bottom of green mud and sand. Bottom temp., 39° F. 18 April, 1891. Several specimens. Off Mexico. Sta. 3430 (lat. 23° 10' N., long., 107° 31' W.). Depth, 852 fms. Bottom of black sand. Bottom temp., 37.9° F. 19 April, 1891. One specimen. In lacking large soft papillae on the elytra this species agrees with H. yoka- hamiensis Mcintosh, now known from near Santa Catahna and adjoining islands and from Monterey Bay off the California Coast as well as from Japan, the type- locahty. From that species it differs clearly in having the peaks of the prosto- mium very prominent, in the greater relative length of the notopodial setae and 58 THE ANNELIDA POLYCHAETA. in the form of the neuropodial setae, especially of the most ventral ones which are reduced and have a characteristic curve or geniculation distally, a detail in which it seems to differ from other species of this group as well. ExJNOE Malmgren. Ofvers. K. vet. akad. Forh., 1865, p. 56, 61. Eunoa Malmgren, Annulata Polychaeta, 1867, p. 6; McIntosh, British annelids, 1900, 1, pt. 2, p. 291. EuNOE EURA, sp. nov.^ PI. 3, fig. 2-6. The dorsum along the middle is brownish, darker caudad; laterally the color is of a distinctly greenish tinge. The" venter is also light brownish but with a greenish cast along a median longitudinal band. Parapodia and setae lighter, yellowish. The body is -broad; it narrows from a httle in front of the middle cephalad; it is broader caudad of the middle than in front of it, narrowing but moderately over about the posterior fourth, the caudal end rounded. The greatest depth of the body is nearly equal to the greatest width exclusive of parapodia (about 8.2 mm.). The depth is uniform over the middle two fourths but decreases conspicuously cephalad and caudad respectively over the anterior and pos- terior fourths. Segments thirty-five in nimiber. Length of type, 45 mm., maximum width, exclusive of parapodia (measured across ventral surface), 8.2 mm., to tips of parapodia, 15.5 mm., to tips of setae, 23 mm. Prostomium widening anteriorly, subcordate but with apex or posterior end bluntly widely rounded; width (2 mm.) a little exceeding the length; the peaks very low and rounded, inconspicuous, each separated from base of median tentacle and more widely from the lateral. Median longitudinal furrow above on prostomium weak, disappearing caudad; on each side a furrow mesad of the rounded elevation, these furrows running caudad and then obliquely caudo- ectad, thus diverging from each other caudad. Eyes none. Ceratophore of median tentacle at widest level one third the greatest width of the prostomium, strongly narrowed distad, at first abruptly and then gradually; length near the total length of the prostomium; above, over basal portion, a longitudinal median fmTow which extends also over part, of prostomiimi, the furrow becoming less distinct caudad. Style missing except for extreme proximal end. Ceratophore ' eiipvs, broad. EUNOE EURA. 59 of lateral tentacles less than half as long as that of the median, half its greatest width; lateral tentacles as wholes manifestly shorter than the prostomium; styles at proximal end as wide or wider than ceratophore, conically narrowed distad, the apical portion slender and acute; no distal enlargement whatever; sensory processes numerous, strictly cylindi'ical, transi^arent. Palps terete, slenderly conical, the tips very slender and acute, the total length about thi-ee and three fourths times as great as that of the prostomium; cilia arranged in longitudinal rows as usual, each small, cylindrical, or sometimes enlarged dis- tally, transparent, arising from a sUght tubercle. (Plate 3, fig. 2, 3). Peristomial parapodia bearing two curved setae; the ceratophores prominent, reaching beyond anterior border of prostomium; styles missing in type. Peri- stomium not evident dorsally. Metastomial somites conspicuously arched above over entire length of body but somewhat more depressed caudad; ventrally less strongly arched. Pygidium very small; no subanal cirri detected. Neural groove sharply defined, rather wide. Nephridial papillae beginning on the fifth somite, on which they are minute; at twelfth and thirteenth somite obviously increasing abruptly in size, which is uniform from there caudad; papillae bending dorsad into the intersegmental furrows. The parapodia of the middle region of the body are very long, being three fifths as long as the width of the somites; stout, little compressed. The noto- podiiun is much smaller than the neuropodium, appearing upon the antero- dorsal surface of the latter as a small lobe near the middle of its length, the distal end of the notopodium falling far short of that of the neuropodium; in the form of a short, somewhat obliquely truncated and but little compressed cylinder which bears the numerous setae on its distal surface and at the caudal the usual finger-like process which is cyUndrically or distally somewhat enlarged, which reaches to near the distal end of the neuropodium, and through wliich the aci- culum extends. Neuropodium strongly compressed subdorsoventrally, thicker at base than distad, the distal edge rising from caudal end cephalad to an angular apex from which arises the finger-shaped process, this being of the same form and size as that of the notopodium, and much shorter than the setae; the aciculmn extends into the process as usual. Ventral cirri arise at middle of length of parapodia. Each, when laid against the parapodium, reaches the apex of the latter, the base of the finger-hke process; the cirrophore is a conspicuously thickened tubercle; the filament is slenderly sub- ulate and smooth. The dorsal cirrophores are large cylindrical processes which lie 60 THE ANNELIDA POLYCHAETA. against the parapodium, being not at all erected; the styles of the dorsal cirri much surpassing the neuropodial setae but when laid back against the dorsum in the middle region falling much short of reaching its middle hne; bearing numerous sensory processes which are cyhndrical and transparent. (Plate 3, fig. 3). In each branch of the parapodium there is a single yellow aciculum; this is stout and long, tapering distad to an acute point; in the notopodium this extends through and beyond the tip of the finger-shaped process, but it does not attain the end of this process in the neuropodium. The notopodial setae are rather numerous, being spread over the entire oblique surface of the process, projecting ectad, increasing in length from those at the inner end to those at the outer or distal ; they are much shorter than the neuropodials and are mostly also clearly more slender; they agree in structure with the neuropodials except- ing that the short, small, apical process is normally bluntly rounded, ending in a slight knob and the pectinate structures are more plate-like, and the pectinae less hair-like. (Plate 3, fig. 6). The neuropodials are numerous and long; each presents a long slender and smooth shaft, above which is a blade clearly, but not greatly wider at its proximal end than the shaft, from which it narrows continu- ously to an acute point; the blade is usually moderately curved; from the base nearly to the extreme apex it bears numerous obliquely transverse rows of hair- like processes; there may be fifty or more of these combs; the naked apex is very short, smooth, and acute. Tips without trace of incision or accessory process. (Plate 3, fig. 4, 5). The setae maintain the same structure throughout the body. Elytrophores occur, as usual, on the second, fourth, fifth, seventh, and alter- nate succeeding ones to the twenty third, on the twenty sixth, twenty ninth and thirty second. They are rather prominent with a suboval scar of which the smaller end is mesad. Unfortunately all the elytra are missing. Locality. Off Peru. Sta. 4,675 (lat. 12° 54' S., long., 78° 33' W.) . Depth, 3,120 fms. 22 November, 1904. One specimen. In lacking eyes this form is like E. abyssorum Mcintosh, the type of which came similarly from a great depth (2,600 fms.) south of Australia. The latter is a smaller species readily distinguished from the one above described by the obvious differences in the setae. Eunoe caeca Moore is another blind species which was dredged in Monterey Bay at a depth of from 861 to 1,062 fms. This is a narrower species differing very conspicuously in the structure of its setae as well as in the form of the prostomium, the form and proportions of the para- podia, and various other featiu-es. LEPIDASTHENIA CURTA. 61 Lepidasthenia Malmgren. Annulata Polychaeta, 18G7, p. 15; Darboux, Bull. sci. France & Belgique, 1900, 30, p. 109. Eumolpe Blainville, Diet. sci. nat., 1828, 57, p. 457 (in part). The most salient character of this genus consists in the great reduction of the elytra, to which the name refers, through which the dorsum is in large measure left naked, and in the rudimentaiy notopodium. The notopodial setae, while usually wholly absent, may be present in much reduced size and numbers in some species (L. irregularis Ehlers, L. argus Hodgson). The. char- acteristic bifid apex of the setae so obvious in most species is present only in the setae of the seventh somite in L. microlepis Potts. Key to Species. • o. Neuropodial setae equal in size throughout each fascia. b. Some notopodial setae present at least on the anterior parapodia L. irregularis Ehlers. 6b. No notopodial setae on any of the parapodia. c. Elytra covering parapodia L. minikoensis Potts. cc. Elytra quite rudimentary, merely capping the elytrophores L. microlepis Potts. aa. Upper neuropodial setae conspicuously difl'erent in size from the lower ones. 6. Upper neuropodial setae greatly enlarged L. elegans Grube. hb. Upper neuropodial setae more slender than the others. c. A few notopodial setae present on at least some of the parapodia L. argus Hodgson. cc. No notopodial setae on any of the parapodia. d. Pairs of elytra above 25; littoral forms. e. A distinct notopodial process on at least the more anterior parapodia. .L. curia, sp. nov. ee. No trace of a notopodial process on any of the jjarapodia L. maculata Potts. Lepidasthenia curta, sp. nov.' Plate 5, fig. 4-9. The body is flattened above and more convex ventrally; below there is a neural furrow and within this a distinct neural ridge. Inclusive of parapodia, it is of uniform width over the middle region, being widest just caudad of middle, but it narrows considerably both at the anterior and posterior end; the body itself, with parapodia excluded, is widest anteriorly and narrowest caudad. The total length of the type exclusive, of the protruded proboscis, is about 27.5 mm.;. greatest width, exclusive of the parapodia, 2.25 mm.; to tips of parapodia and exclusive of setae, 4.4 imn.; inclusive of setae, 6 mm. or a little more. The number of somites is fifty-six. ' curtu.s, short. 62 THE ANNELIDA POLYCHAETA. The prostomium is covered above by the transparent first and second elytra. It is trapeziform or subhexagonal with the transverse diameter or width exceeding the length. It is widest a Uttle behind the middle where it bulges on each side. Upon the bulging lobe on each side is borne a large eye. The posterior eyes are much smaller and closer together and each is close to, and in life may possibly be covered by, the base of the parapodium of the first meta- stomial segment. The ceratophore of the median tentacle is inserted in an incision in the middle of the anterior border; its base extends caudad in a narrow- ing, wedge-shaped process; it narrows subconically distad to the truncate end, on which is inserted the style; the style is long, though it is shorter than the palps, fully three times as long as the prostomium; it narrows continuously from the base to the slender and acute tip; without any evident subterminal enlargement; the ceratophores of the lateral tentacles are inserted farther forward; each is subcylindrical, but narrows distad like the median; the distal end of the ceratophore is much thicker than the base of the style; the style is shaped Uke that of the median tentacle but is shorter. The tentacles are pale without any evident darker markings in the type as at present. The palpi are a Uttle longer than the mecUan tentacle; each is terete and acuminate, and ends in a slender thread-hke tip. (Plate 5, fig. 4). The ceratophores of the parapodia of the peristomium extend forward about to the level of the anterior border of the head; the styles are of the form of the tentacular styles but are somewhat longer than the median of these. The extended proboscis is 4.2 mm. long and 2.5 mm. thick. The metastomial somites are distinct. They are of similar form and structure throughout. The pygidium is minute and subcyUndric; anus terminal. The nepliridial papillae are situated on the bases of the parapodia; each is borne at the caudal edge and is a slender, cylindrical tube of white color which bends dorsad in the intersegmental cleft. The parapodia in the anterior region are only half, or but little more, the width of the body proper; but in the median and posterior regions they fully equal the width of the somites to which attached. From the base outward they are subcyhndric or sUghtly narrowing distad, the distal end conically attenuated and rounded. At the distal end is a larger, distally rounded, postsetal process and a much more slender, cyUndi'ical, presetal process, the setae emerging between these processes. The notopodium appears on the anterior parapodia as a short and slender cylindrical process into wWch an aciculum extends; this becomes lower caudad and in most segments is not evident as such. The LEPIDASTHENIA CURTA. 63 dorsal cirrus is attached caudad of the middle of the parapodium and extends distad to or a little beyond the tips of the neuropodial setae; it is terete and acuminate to a fine tip like the tentacles and tentacular cirri; the cirrophore is a thick and conspicuous eminence. The ventral cirrus is attached distad of the middle; it is a short, slender, subulate process not reaching to the end of the neuropodiimi. No notopodial setae detectable on any parapodia of the type. The neuro- podials are arranged in subvertical series which may embrace eighteen to twenty- fom- setae spreading out from each other distally. In the tyi^e they are colorless. There are two types of neuropodials which are the extremes in a series in the parapodia of the middle region. The most dorsal setae are longer and pro- portionately more slender; the distal pectinate division is longer and more slender, from the thickened proximal end narrowing to a long and slender tip. The more ventral, shorter, setae have the heads or pectinate division propor- tionately stouter and shorter, these curving moderately, the concavity on the non-pectinate side. The tip is bifurcate, the principal tooth short and stout, convex on one side, opposite the pectinae; the minor tooth is much smaller, acute, curving a httle away from the principal one. In going caudad the setae become shorter and stouter, the pectinate terminal division being markedly proportionately stouter and shorter. Cephalad the setae become of the more slender type. (Plate 5, fig. 7-9). The elytra are small as usual, leaving much of the dorsum uncovered. Each is thin, transparent, wholly smooth and subovate (anterior) or more conmaonly subelhptic in outUne. (Plate 5, fig. 5, 6). They decrease m size caudad. The precise number could not be determined with entue certainty but is either twenty-seven pau's or very near that number. Locality. Off Mexico. Sta. 3424 (lat. 21° 15' N., long. 106° 23' W.). Depth, 676 fms. Bottom, grey sand with black specks. Bottom temp., 38° F. 18 April, 1891. One specimen. The specimen unfortunately seems at some time to have been dry. In comparison with L. irregularis Ehlers (Zool. jahrb. Suppl., 1901, 2, p. 255) from the south Chilean coast, this is seen to be a much shorter form with but fifty-six parapodia bearing somites as against eighty-seven in that species. The parapodia are proportionately much longer. The elytra are colorless, thin and transparent whereas in irregularis they are thick and dark grey or black. The tentacles are more slenderly and uniformly acimiinate as are also the palpi, not abruptly narrowed to the slender tip. The setae are much more numerous and differ in details of structure. 64 THE ANNELIDA POLYCHAETA. Iphione Kinberg. Annulata nova, 1855, p. 12; Fregatt Eugenics Resa. Zool. Annulater, 1857, p. 8; Darboux, Bull. sci. France et Belgique, 1900, 30, p. 108. Eumolphe Blainville, Diet. sei. nat., 1828, 57, p. 457 (in part). IphioncUa McIntosh, Challenger Annelida, 1885, p. 58. Iphione ovata Kinberg. Ofvers K. vet. akad. Forh., 1857, 14, p. 383; Fregatt Eugenics Resa. Zool. Annulater, 1857, p. 8, pi. 3, fig. 8, 8a-8h; 1910, pi. 10, fig. 45, 45e; Baird, Journ. Linn. soc. London. Zool., 1865, 8, p. 181. Locality. Paumotu Islands: Rangiroa Island, Mohican Reef. 23 Sep- tember, 1899. One specimen. The specimen, which, Uke those of various related species, presents a strik- ing resemblance to certain chitons, is 17 mm. long and 10 mm. wide across the middle. Kinberg's type, taken on Oahu near Honolulu, is a considerably smaller specimen, its measurements being given as 12 mm. long and 7 mm. wide; but in other respects the Rangiroa specimen agrees essentially with Kinberg's account so far as it goes. Admetella Mcintosh. Challenger Annelida, 1885, p. 124; Darboux, Bull. sci. France & Belgique, 1900, 30, p. 103. Admetella hastigerens, sp. nov."^ Plate 9, fig. 6-8. In the preserved type there are no distinctive features in the coloration. The body throughout is a grayish yellow. The acicula and setae are yellow, the acicula in part darker, more bronze colored. The body is fusiform, being conspicuously narrowed from the middle toward each end, the caudal and cephalic narrowing being equal or very nearly so. Convex both above and below but the venter mesally with a wide and conspicuous neural depression or furrow in which is a large neural ridge. In- tegument thin and transparent along a well-defined median longitudinal band. Total length of type, 80 mm. ; greatest width, exclusive of parapodia, 8.5 mm. ; to tips of parapodia, about 20 mm.; to tips of acicula, near 27 mm. The num- ber of segments is sixty-eight to seventy. Prostomium decidedly wider than long, being transversely oblong; the ' hasta, lance, and gcrere, to bear. ADMETELLA HASTIGERENS. 65 length (about 1.5 mm.) about three fourths the width (2 mm.). Constricted at the base. Bulging out on each side, a large rounded prominence which shows a darkening but no evident eyes. The anterior margin is wide and nearly straight, with no median incision. The ceratophore of the median tentacle arises caudad of the middle; it is large, and on each side has a very conspicuous extension from its base. Each lateral extension is connected with the cera- tophore by a narrow isthmus beyond which it is swollen, conical, and projects upward and forwards distally. Above the swollen portion adjacent to the isthmus it Ls narrowed conically to a slender filament of moderate length; the total length of the appendage is apparently less than twice the length of the head ; these appendages correspond to the tentacular scales noted by Mcintosh in his description of A . longipedata and as corresponding to those in the Sigalionidae. The lateral tentacles, or antennae, are broken off; each is inserted on the anterior face near the ectal corner, and apparently projected directly cephalad; what appears to be a portion of the style of one was found adhering to the border of the mouth, this is a slender terete body ending in a slender filament not preceded by an enlargement. The palpi are large, terete, and gradually acuminate, the tips very slender and ending in a filament which seems to be easily caducous; smooth; near 1 mm. thick at base and 8 mm. long, or six times the length of the prostomium. (Plate 9, fig. 6). The peristomium is slightly exposed above as a narrow transverse fold caudad of prostomium. The ceratophores of its parapocUa are prominent. The metastomial soinites are all distinctly differentiated; those of the anterior and middle regions of a nearly uniform length (width in anterior region near 3.4 times the length, in the widest middle region near 4.8 times), in the caudal region decreasing conspicuously. Pygidium small, pointed. The ne- phridial papillae arise at each ectal end of the ventral surface of the somite at the middle adjacent to the parapodium rather than at the caudal edge, as more usual, the caudal margin of the somite more or less extended immediately mesad of the papilla; they begin on the sixth somite; the anterior ones are small, sub- cylindrical structures somewhat narrowed distad and then a little flaring about the terminal face, each extending caudad and a little dorsad into the inter- segmental cleft; farther caudad the papillae become conspicuously, stouter, decreasing again in the caudal region. The elytra are all missing. The elytrophores are mostly conspicuous, with the usual somewhat ear-shaped scar. They occur on the second, fourth, fifth, seventh, and alternate soinites to the twenty fifth, then on the twenty seventh, 66 THE ANNELIDA POLYCHAETA. twenty ninth, thirty second, thirty fifth, thirty eighth, forty first, forty fourth, forty seventh, fiftieth, fifty third, fifty fifth, fifty seventh, sixtieth, and possibly on one or two others, the condition of the caudal end making it difficult to be certain; the total number is thus a little above twenty-five pairs. The parapodia are conspicuously elongate as in the inunediately related forms, each, exclusive of its acicular process, being about as long as its somite and, inclusive of this, much longer. Each is, at its broad base, strongly com- ' pressed in an anterocaudal direction; in view from cephalic or caudal side, it is seen to narrow strongly to near the middle of its length, from where the neuro- podial branch continues of nearly uniform width to the distal end which is obhque, its anterodorsal end elevated, and the aciculum passing through it. The noto- podium is a small but clearly separated lobe arising on the dorsal surface near the base of the neuropodium; the ventral edge of its distal end is prolonged into a slender acicular process similar to that of the neuropodium ; the aciculum shorter and more slender than that of the nem-opodium. The parapodial cirri are all lost and nothing definite concerning them can be affirmed from examination of the type. There is a single aciculum in each branch of the parapodium. The noto- podial aciculum is yellowish, the coarser and longer neuropodial dark brown. Both acicula project widely beyond the tips of the acicular processes. No notopodial setae are detected in the type. On the distal end of the neuropodium is a group of fine, delicate, and transparent setae which are very much shorter than the projecting ends of the acicuh. These setae are flattened structures of vitreous appearance; viewed from broad surface each is seen to be parallel- sided from the base to a triangular tip of which one side is nearly straight, the other oblique; the tip is entire, not at all incised or bifid, though it is weakly indented or notched at the base on its more oblique side and less so on the opposite one; serrations occur along both borders, and along the ridge the arrangement and development of these is very regular, the serrations not devel- oped on the acuminate terminal division or these vaguely developed on the more obhque side alone; the thickened serrate edges seem to be bent up as far as the tip so that the seta appears concave; in side view the seta is narrow, the tip, over which the serrate thickened borders do not extend, appearing abruptly much thinner and very acute. (Plate 9, fig. 7, 8). Locality. Off Panama: Sta. 4,621 (lat. 6° 36' N., long. 81° 45' W.). Depth, 581 fms. Bottom of green sand. Bottom temperature, 40.5° F. 21 October, 1904. One specimen. ADMETELLA DOLICHOPUS. 67 This species in its general structure much resembles A. longipedata Mcintosh, secured by the Challenger from near Prince Edward Island (1,378 fms.)- It is Uke this species in having no notopodial setae, the long protruding aciculum being alone present; but the notopodial branch is more distinctly developed and arises farther proxunad, the acicula extend farther beyond the parapodial lobes proper, and the ventral setae lack- the characteristically bifid apex of those of A. longipedata. Admetella renotubulata (Moore), described from a specimen taken off Santa Catalina Island (2,196-2,228 fms.), is also evidently a closely related species; but it is readily separated by the clearly different form of the nem-opodial setae, and the presence of notopodial setae, -the latter not having been detected in the other two species. All these species lack pigmented eyes, though structures possibly representing modified eyes are noted in renotubulata. Admetella dolichopus, sp. nov.^ Plate 10, fig. 1. There is nothing distinctive in the coloration of the preserved specimen, the body appearing obscure yellow, the parapodia a somewhat Ughter yellow, and the acicula nearly colorless. The body is fusiform, in general as in hastigerens, but the caudal region is more strongly narrowed, becoming slender and subacutely pointed. The dor- sum is convex; its integument presents a thinner, middorsal, longitudinal stripe which is semitransparent. The venter is more depressed; it has a wide longi- tudinal neural furrow in which lies a conspicuous neural ridge as in the preceding species. Total length of the type 60 nmi.; greatest width, exclusive of the parapodia, about 5 mm.; to ends of extended parapodia, exclusive of acicular processes, near 20 nun. ; to ends of acicula, near 24 mm. Total number of somites in the type sixty or mthin one or two of that number; in the paratype, fifty-seven. Prostomium about two thirds as long as \vide, transversely oblong, the anterior margin straight or nearly so between the widely separated ceratophores of the lateral tentacles; on each side posteriorly a prominent lobe projects laterad, neither this lobe or any other part of the prostomium showing any trace of pigmentation. The ceratophore of the median tentacle is a very large body inserted dorsally caudad of the middle of the prostomium; its diameter proxi- mally is equal to half the greatest width of the prostomium as a whole; it - 60X1x05, long, ?roOs, foot. 68 THE ANNELIDA POLYCHAETA. is rounded and narrows abruptly above to the level of base of the style; at each anterolateral corner it is extended as a prominent, distally gradually narrowing ridge reaching to the anterolateral corner, these ridges corresponding to the large free lobes attached to the ceratophore in the preceding species; style missing in the type. The ceratophores of the lateral tentacles are attached near the anterolateral corners, each projecting slightly ectad of directly forwards; the ceratophore is a very short, proportionately thick, cylindrical body; the style is abruptly much thinner, its length not far from twice that of the prostomium; it narrows gradually distad to a moderate, subterminal, fusiform enlargement beyond which is a slander terininal filament. The palpi in the type are near 9.5 mm. long, or seven or a little more times as long as the prostomium; each is terete and slenderly tapering, subulate, ending in a rather fine tip. (Plate 10, fig. 1). The parapodia of the peristomium project on each side in the usual position; the ceratophores of the cirri reach forward about to the level of the anterior margin of the head; the dorsal cirri are much longer than the lateral tentacles but considerably shorter than the palpi; each has the form of the style of a lateral tentacle. The metastomial somites are all clearly differentiated below, less distinctly above; they are comparatively long, in the widest part of the body being near one third as long as wide; they are of nearly uniform length over most of the body but in the most caudal region decrease to the pygidium as in the preceding species. The anus is terminal or slightly more dorsal, its border radially ridged or tubercular, no styles present in the type. The nephridial papillae in the anterior region are very minute and at first scarcely evident; in the middle region they are much larger but still comparatively small; each is subconical with the narrowed tip bent a little dorsad as usual ; each is attached at the extreme caudal margin of the somite. The elytra are all missing from the type-specimens. Elytrophores promi- nent, borne on the base of the parapodia and movable with these; present on somites II, IV, V, VII and alternate somites to the twenty fifth as usual, then on the twenty eighth, thirty first, thirty fourth, thirty seventh, fortieth, forty third, forty sixth, forty ninth and fifty second and what seems like the fifty third, the total being twenty-three. The parapodia are much elongated, each, exclusive of aciculmn, being much longer than the width of the somite to which attached as indicated by the measurements previously given. Each is strongly flattened in the cephalo- ADMETELLA DOLICHOPUS. 69 caudal direction; each narrows strongly from base to near the middle of the length, the proximal region in outline subtriangular, its dorsal side strongly slanting, its ventral horizontal and continuous in direction with that of the remaining more slender portion of the parapodium. Neuropodium long, but Uttle varying in thickness in different parts of its length except toward the distal end where subconically narrowed, the distal end obUque with acicular process at the more projecting dorsal corner. The notopodium is a distinct, well- separated lobe, subcylindric at the base and distaUy formed much like the neuro- podimn, which arises on the dorsal surface a little distad of the middle of the parapodium. At the base of each non-elytrophorous parapodium there is above, a characteristic, short, distally rounded, subcyUndric process. Just proximad of the notopodiimi is the dorsal cirrus, which from the traces alone left in the type, seems to have been small. The ventral cirri are also lost excepting on a few anterior j^airs; on the second metastomial parapodia the cirrus is attached near or a little distad of the middle of the length, and extends clearly distad of the end of the parapodium; on the following pair of parapodia the cirri are shorter and scarcely exceed the neuropodium proper distally, though on one side the cirrus of the third somite is elongated like that of the second; the cirrus is slender with a sUght subterminal thickening and a fine terminal filament. The acicula are pale, more or less vitreous in appearance. Each projects but moderately beyond its slenderly conical process, very much less exposed than in the preceding form; distally it is very fine and easily bent back into a curl. All setae appear to have been broken off, no complete ones being detected in either of the types. Locality. Off Mexico: Sta. 3425 (lat. 21° 19' N., long. 106° 24' W.). Depth, 680 fms. Bottom of green mud and sand. Bottom temp., 39° F. 18 April, 1891. Two specimens. Characterized especially by the form of the lateral prolongation of the median ceratophore; instead of rising free from the prostomium as in the pre- ceding species, these extend as simple but conspicuous ridge-hke elevations out to the bases of the lateral tentacles. The feet are relatively decidedly longer than in hastigerens, each in length much exceeding the width of the somite to which attached. The forms of the notopodial processes and especially of the basal dorsal processes of the interelytrophorous somites are characteristic. 70 THE ANNELIDA POLYCHAETA. PoliYNOE Savigny. Descript. Egypte. Hist, nat., 1809 [= 1822], 1, pt. 3, p. 20; McIntosh, British annelids, 1900, 1, pt. 2, p. 389; Darboux, Bull. sci. France & Belgique, 1900, 30, p. 11. Lepidonolus Quatrefages, Hist. nat. annel('s, 1865, 1, p. 257 (in part). Parapolynoe Czerniawsky, Bull. Soc. imper. nat. Moscou, 1822, 57, p. 187. POLYNOE INNATANS, Sp. nOV.^ Plate 8, fig. 1-7. Pale and semitransparent. The body is widest in front of the middle and from there widens very grad- ually caudad and more abruptly cephalad. The greatest width, exclusive of the parapodia, is 1 mm. ; inclusive of parapodia, but without setae, 2 mm. ; to tips of setae, 3.5 mm. Length 9.5 mm. Prostomium decidedly wider than long; divided by a median longitudinal furrow; bulging on each side in the usual manner. Eyes large, black, distinct, the anterior the larger and much farther apart ; posterior eye on each side close to anterior, separated by much less than its diameter. Median ceratophore attached somewhat higher up or more dorsally than the lateral, longer than the latter, narrowing distad; style, which in the type is detached, much larger than the palps, cylinch-ical, narrowing to a fine filament distally, sparsely, minutely spotted with dark, and more sohdly darkened near the middle. The cerato- phores of the lateral tentacles more cylindrical, short; the styles extremely short, narrowed abruptly to a fine terminal filament which about equals in length the proximal division and ceratophore together; the entire lateral tentacle, inclusive of its ceratophore, does not greatly exceed the prostomium in length. Palps short, abruptly narrowed distally in a conical tip. The parapodia of the peristomium extend obhquely cephaloectad as usual; the ceratophores reach or extend a little in front of the level of the anterior border of the head proper. At least one conspicuous curved seta. The styles of the cu-ri are cylindrical and slenderly acuminate distad, the dorsal exceeds the ventral, and both exceed the palps. Segmental papillae arranged as usual. Each is situated at the base of a parapodium at the caudal edge and is a short conical process ending in a narrower subcyUndrical short tip which bends a little dorsad, the papilla as a whole extending caudoectad. ' innatare, to float. POLYNOE INNATANS. 71 Parapodia shorter than the somite to which attached, decreasing in length cephalad and caudad. A typical parapodium is deep dorsoventrally at the base and outward to the low, stout notopodial process which is distad of the middle; the neuropodium beyond the notopodial elevation narrows subconically ; distally it is obliquely subtruncate and is extended above into a short, slender, finger-like process. The dorsal cirrophore is a stout, subconical joint arising just proximad of the iniddle; no styles were found in the type, all appearing to have been lost. The ventral cirri are attached toward the distal end close to the setae; the cirro- phore is a thick, rounded lobe; the style is smaller at the base, then conspicuously and continuously narrowing to the slender tip ; extending well beyond the distal end of the neuropodium but not reaching the tips of the setae. Ventral cirrus of the first metastomial parapodia attached farther toward the base, much longer than the others, and attaining or nearly attaining the distal ends of the setae. Most of the elytra are missing from the type. Those present are thin and transparent. They extend outward on the parapodia as far as the notopodia, the setae of which extend from beneath the outer edge of the elytra. Elytra well overlapping both mesally and anterocaudally. The elytra are subcircular, with two or more weak notches on the exterior side opposite the notopodial fasciae. The exterior and anterior parts of the elytra are nearly uniformly covered with numerous, small, low tubercles each of which has a somewhat hemispherical basal portion and an abruptly narrower short, conical, apical por- tion which is conmionly bent toward one side. The acicula are colorless. The notopodial is stouter than the neuropodial, but shghtly curved, its acute apex protruding among the setae. The neuropodial typically presents a more distinct and double curve; its acute distal portion extends through the finger-Uke process of the neuropodium. The notopodial setae are arranged in a whorl on the distal end of the notopodium; they are typically ten to twelve in number; there are two principal types, a posterior group of larger, weakly and evenly curved setae, and an anterior group of smaller ones most of which are abruptly bent at the beginning of the pectinate distal division and are much the widest in the region of the head and somewhat boom- erang-shaped. The notopodials of the first type have over the distal portion along the convex edge a series of mostly near eight scales which are widely separated; the tip. is distinctly bifid, but is frequently broken off. (Plate 8, fig. 2). Those of the second type have along the convex edge distad of the bend a series of mostly near twelve more closely arranged scales; the tip weakly bifid. (Plate 8, fig. 1). The neuropodial setae are much more numerous, 72 THE ANNELIDA POLYCHAETA. commonly near twenty-five in number. They are also much more slender than the notopodials. Each has a long slender shaft and a head or distal scale-bearing division which is enlarged at the proximal end and runs out to a slender acute tip like the head of a spear; in one view the seta is a little curved proximad of the head; along one side of the head (the side of the convexity of the seta) are two rows of scales and distad of these there is a distinct subapical tooth. (Plate 8, fig. 6, 7). In the more anterior setae the heads are much shorter than in the posterior ones. (Plate 8, fig. 5). In addition there is a third type of notopodial setae; these are longer and stouter than the others and are straight; they are acuminate distad in the usual way; in place of a single series of pectinae there are five or six ranks of these. (Plate 8, fig. 5). None of this third type was found cephalad of the eighth (seventh meta- stomial) segment, in the fascia of wlaich two were noted, but they occur on the segments caudad of this and project conspicuously beyond the others. Locality. Between Galapagos and Paumotu Archipelagos: Sta. 4728 (lat. 13° 37' 40" S., long. 114° 22' W.). 19 January, 1905. One specimen taken at 300 fms. to surface. This species is well characterized by its remarkably reduced lateral tentacles, the character of the elytra and their papillae, and the structure of the setae. POLYNOE NESIOTES, Sp. nOV. Plate 8, fig. 8; Plate 9, fig. 1-5. The body is short and compact, exclusive of the parapodia having its greatest width at about the ninth somite, from where it narrows very slightly cephalad and gradually caudad; inclusive of parapodia the greatest width is a little farther caudad; the dorsal surface appearing flat with the parapodia rising obliquely at the sides; the ventral surface is smooth, a wide neural ridge present. The total length at present is about 22 mm.; the greatest width, exclusive of the parapodia, 3 imii. ; inclusive of the parapodia but without setae, 4.6 mm.; over all, 5.6 mm. Number of somites thirty-four. The color of the body at present is dark brown, but as the specimen appears at some time to have been dry this is scarcely of significance. The neuropodial setae are pale yellow; the notopodials colorless or white. The prostomium is so shrunken in the type that its original form cannot be stated. The ceratophores of the tentacles are cyhndi'ical and parallel, the median a httle exceeding the lateral. The tentacles are comparatively thick; POLYNOE NESIOTES. 73 they appear to have ended in an abruptly more slender terminal filament. The palpi end in slender tips. The prostomial appendages in the type are deformed from shrinkage and so cannot be more fully described. The parapodia of the peristomium bear two or more setae above. The cirri are thick and cyUndrical like the tentacles and similarly have a reduced tip. The metastomial somites are distinctly separated. They are of nearly uniform length excepting at the caudal end of the body where they are reduced. The pygidimn is a small short process bearing distally two anal cirri of the general form of the parapodial cu-ri and each with a subapical dark annulus. The parapodia are moderately short and stout, distally conically narrowed and compressed cephalocaudally; the ventral surface is less slanting than the dorsal. The notopodium appears as a small but distinct tubercle on the dorsal surface of the neiu-opodium near the middle; its setae, much finer and paler than the neuropodials, do not reach the end of the neuropodium. The ventral cirrus is attached proximad of the middle of the parapodium; it is short and acuminate, ending in a slender tip and falUng much short of attaining the end of the neuropodium; the ventral cirri of the parapodia of the second somite, how- ever, are, as usual, much longer, each being stout, terete, and uniformly acuminate to a slender acute tip which surpasses the setae. The dorsal cirrus of a typical parapodimn has a stout, subconical cirrophore; the style is terete and distally subulate, narromng gradually to a slender, acutely pointed tip; distally there is a broad, black annulus and some of the cirri, at least, also appear darker towards the cirrophore; the cirrus extends beyond the distal end of the parapodium. A single stout aciculum in each ramus, that of the neuropodium emerging toward the dorsal side of the end. The notopodial setae are much finer and shorter than the nem'opodials. They form a small but conspicuous white fascia, the setae of which do not attain the distal end of the neuropodiimi. Each noto- podial is thickest proximally and narrows distally regularly to a slender and very acute tip ; excepting for a smooth slender tip and the proximal end, there is along the entire length a series of transverse scales or plates in which divisions are indicated by longitudinal lines, but the teeth non-divergent, closely appressed; the plates are close set and overlap much; they afe evident all along one side but usually are e\'ident only more distally on the other or in some in certain views may not project on the opposite side at all. The medulla is finely fibrillar as usual. There is a tendency for much foreign material to adhere to the noto- podials. The neuropodials greatly exceed the notopodials in thickness and length. Each neuropodial has a smooth shaft, which is slightly curved between 74 THE ANNELIDA POLYCHAETA. the point of emergence and the head or pectinate division toward which it thickens shghtly. The head is bent at a small angle to the shaft as usual. It narrows to a rounded point distad and is gently concave on the side bearing pectinae and coiivex on the opposite ; it presents an acute subapical tooth which diverges but little from the principal tooth. The pectinae extend about half- way from the base to the apex, sometimes a little more and sometimes a little less. (Plate 8, fig. 8; Plate 9, fig. 1, 2). The elytra are firmly attached and are strongly imbricated. Those of the first pair are small and subcircular in outline; a rather narrow border on each is smooth or only very minutely granular, while the large area within is thickly studded with large tubercles or papillae which are subcorneal, the distal portion being softer and a basal portion denser and more opaque and appearing by itself hemispherical; the papillae seem to be all of the same type excepting for varia- tion in size, those toward the periphery of the papillose area becoming smaller. The succeeding elytra become much larger in size and are more elongate, being broadly subelliptic to subovate. On the second elytra large papillae similar to those of the first occur over and immediately adjacent to the area of attach- ment, but elsewhere the papillae are much reduced and anteriorly especially are sparse, leaving considerable areas smooth. Toward the middle region and farther caudad the elytra become almost smooth, losing the larger papillae, while the smaller ones become reduced to minute granule-like bodies which may be present only on restricted areas of the surface. There are fifteen pairs. (Plate 9, fig. 4, 5). Locality. — Lower California: Santa Margarita Island. Exped. 1891. One specimen which at some time had apparently been dry. As a species characterized especially by the structure of the setae and elytra. Lepidonotus Leach. Ann. philos, 1819, 14, p. 205; DARBOtJx, Bull. sci. France & Belgique, 1903, 30, p. 109 (in part); Mc- Intosh, British annelids, 1900, 1, pt. 2, p. 273. Eumolpe Blainville, Diet. sci. nat., 1828, 57, p. 457 (in part). Lepidonotus johnstoni Kinberg. Ofvers, K. vet. akad. Forh., 1855, 12, p. 381; Fregatt. Eugenies Resa. Zool. Annulater, 1857, pi. 4, f. 13-1.3b; 1858, p. 12; 1910, pi. 10, f. 15; Baird, Journ. Linn. soc. London. Zool., 1865, 8, p. 182. Locality.— Off Panama: Perico Island. Shore. 26 October, 1904. One specimen. LEPIDONOTUS NESOPHILUS. 75 This is the type-locaUty for the species, Kinberg stating that his specimens inhabited "litora insularum prope Panama." Lepidonotus NESOPHILUS, sp. nov.^ Plate 4, fig. 1-7; Plate 5, fig. 13. The general form of the body is rather slender for this genus, the outline as seen from above being narrowly oblong; the sides straight from near the end of the anterior fourth caudad, more strongly so near the caudal end, where the venter proper is seen to run to an acute point; narrowed also a little cephalad from the level of greatest width, the anterior end convex. Dorsal and ventral surfaces moderately and about equally convex. The total length of type is 27.5 mm.; the greatest width, exclusive of the parapodia, is 4.8 mm.; inclusive of parapodia, 7 mm.; and inclusive of the setae, 8.2 mm.; the width across dorsum to the edges of the scales is 6.8 mm. ; and the greatest depth of body is 4.2 mm. The color of the elytra is greyish green, paler toward the ectal side; a larger light spot is over the point of attachment and numerous srnall light dots about this. The color of the venter and of the dorsum where exposed along the mid- dorsal line is more dilute and with less suggestion of gi-een. The setae are brown, darker at the tips. The prostomimn is convex with the sides behind well rounded; in front it presents the two conspicuous, subcylindi'ical processes forming the lateral ten- tacular ceratophores, each lateral half of the prostomimn inclusive of these cera- tophores being somewhat pyriform, a shallow longitudinal median furrow bisecting it above. The surface is weakly transversely wrinkled. Eyes black. General surface pale in contrast with the ceratophores, which are blackish. (Plate 4, fig. 1). Ceratophore of median tentacle thick, subcylindrical, widening distad, half the length of the prostomium proper. The style is only twice as long as the prostomium, strongly tapering from the base distad, with the usual sub- terminal enlargement which is elliptic in outhne, this followed by the slender apical filament which about equals the subterminal enlargement m length; the style is blackish but with a light colored annulus just proximad of the enlarge- ment and the terminal filament again pale. Ceratophore of the lateral tentacle four fifths or more the length of the ' >'T]l\os, loving. 76 THE ANNELIDA POLYCHAETA. median ceratophore, and about three fifths as thick distally. The ceratophore and filament are blackish with the light subterminal and terminal portions as in the median tentacle. The lateral tentacles are decidedly more slender than the median and are about two thirds as long. (Plate 4, fig. 1). The palpi are stout structures projecting laterally beyond the prostomium; they are much thickened or swollen a little above the proximal end, where they narrow evenly and conspicuously to an acute point, but present no abruptly thinner apical filament. In length they about equal the median tentacle. They are pale throughout. The parapodia of the peristomium are long, reaching much beyond the tip of the tentacular ceratophore, the portion distad of this level being fully three fourths the length of the ceratophore. The cirri agree in form and color with the tentacles; the dorsal cirrus is rather longer than the lateral tentacle and ventral one clearly and considerably shorter than the dorsal. (Plate 4, fig. 1). The body, as usual, has twenty-five setigerous somites following the peri- stomium. The nephridial tubercles begin on the sixth somite. On this somite the tubercle is short and inconspicuous but on the others the tubercles are promi- nent; each projects ectocaudad and ventrad and at the distal end is clavately swollen and may curve more strongly ventrad. A pair of low dorsal tubercles occur on somite I and also less prominently on II and III, but on succeeding somites none are evident in the type. There are the usual twelve pairs of elytra occurring on somites II, IV, V, VII and succeeding odd numbered somites to XXIII. The elytrophores are prominent, cylindrical or subcylindrical trunks with broadly elliptic cross-section, or these somewhat flattened or indented on one side; similar but more rounded prominences occur on the somites not bearing elytra. The elytra are broadly subelliptic membranous scales of moderate size with their long axes in situ in most oblique. They may meet at the middle of the dorsum but do not overlap and may have a narrowed naked stripe between them; the elytra in the series on each side overlap a little but the imbrication is not particularly strong. On the first elytra there is a series of rounded bosses or tubercles along the caudal border and continuing along the ectal but not the mesal end; those over the middle of the series are large and the others decrease in size from there both ways; these tubercles are separated by a distance mostly two or three times then- own diameter; in front of this submarginal series, over the dark areas of the surface and also over the area of attachment, are scattered other similar rounded or hemispherical tubercles of large size with among them similarly LEPIDONOTUS NESOPHILUS. 77 formed ones of smaller size; over the light area along the anterior and ectal border there are numerous tubercles of mostly very small and minute size. On scales farther caudad the surface becomes almost wholly smooth, the large tubercles being wholly absent and a few very small ones with more numerous minute points confined mostly to the ectocaudal border within the fringe. Along the ectocaudal edge of the elytron there is a series of short and slender transparent rods projecting freely from the edge. (Plate 4, fig. 2, ,3, 6). The tubercles vary from hemispherical to forms constricted at the base and so more nearly spherical. The tubercles are densely spinescent, the spines being proportionately longer and coarser on the smaller tubercles. (Plate 4, fig. 4, 5). Each typical parapodium presents a stout, strongly conical neuropodium which is slightly rounded or obUque across the distal end from wliich the setae project. From the anterodorsal surface of the parapodium the notopodium projects as a small lobe. The ventral cirrus is a short, acuminate process the tip of which, when the cirrus is extended against the neuropodium, reaches the bases of the neuropodial spines. The dorsal cirrus is about three tunes as long as the ventral; it presents a stout subcorneal ceratophore which is about one third of the total length ; the filament is of the same form as the tentacular cirri and tentacles, presenting a subterminal enlargement and terminal filament; the cirrus is pale tliroughout except for a blackish annulus over the base and one proximad of the subterminal enlargement. The ventral cirri of the first parapodia as usual are much longer than the others. The anal cirri are broken off in the type-specimen. The notopodial setae are either straight or, more typically, curved over theii- exposed portion. The exposed portion widens from the base to near the middle of the length and then narrows distad to a point. Each seta appears in surface view bipinnate, there appearing a fringe of close-set transparent fine teeth along each side, but those of the convex side are decidedly longer and extend along the seta farther than those of the opposite side. There is a series of longitudinal lines or teeth across each segment as shown in Plate 4, fig. 7, these decreasing in length from the convex side to the concave. Only one type of seta was noted. The cortex shows a jointing, the cross-lines being distinct and closely arranged and corresponding to the serrations. (Plate 5, fig. 1). The neuropodial setae are longer and much coarser than the notopodials, 78 THE ANNELIDA POLYCHAETA. as usual. The tip in those of the anterior somites is as long as the serrate portion below it; it is but slightly curved, being convex on the abdental side and nearly straight on the (Jentiferous, on which side is present a characteristic obtuse angle a short distance below the apex, from which a slender tooth normally projects distad; this tooth is easily lost; this subapical tooth was not found in setae of posterior segments. The teeth of the most distal row are long, stout, and acute; this row is followed by five to nine small series of teeth which dimin- ish in size proximad. (Plate 5, fig. 2, 3). Locality. — Galapagos Archipelago : Chatham Island. 8 January, 1905. One specimen taken on the shore. A well-marked species easily distinguished by its general form and the size, structure, and relations of the elytra as well as by the structure, propor- tions, and coloration of the prostomium and its tentacles and palps, and the structure of the setae. It approaches L. versicolor Ehlers of the Chilean Coast but differs conspicuously in its much stouter and differently formed palps, the proportions of the other anterior appendages, form of head, structure of the elytral tubercles, the larger smooth tip of the neuropodial setae and in other details. Aphroditidae. In this family the body is proportionately broad and short, having an oblong or subelliptic outhne; depressed, with dorsum arched and venter flat. Prostomium distinct. Eyes usually two pairs, either sessile or pedunculate. A single median tentacle with beneath it a distinct facial tubercle. Lateral tentacles none, or rarely present (in Triceratia only). A pair of large palpi. Peristomium bearing two pairs of long tentacular cirri and mostly setigerous. Parapodia biramous, some bearing dorsal cirri and others elytra in their place. The elytra occur on somites II, IV, and V, and on most of the succeeding somites in alternating groups of twos or in the posterior region in part in groups of threes; usually imbricated. Setae all simple, strongly developed. The dorsal setae long, consisting of stout spines and finer capillary forms, directed typically upwards and backwards over the elytra and dorsum. Capillary setae often iridescent, with hair usually more or less felted over the dorsum and covering the elytra. Pygidium bearing two anal cirri similar to the ordinary notocirri. The proboscis bears no jaws, or these but rudimentary, ordinarily repre- sented merety by thickened muscular prominences. APHRODITA. 79 The aphroditids, while occurring to some extent in the shallow water along the shores, live for hj far the most part at greater depths. The Albatross dredged Laetmonice wyvillei from the excessive depth of 3,120 fathoms. Both the bathymetrical and the geographical range \vith certain species is very great. Another species of Laetmonice, L. benthaliana Mcintosh, has been taken at only twenty-six fathoms on the one hand, and on the other, at 2,900 fathoms (Chal- lenger AnneUda, 1885, p. 40, 45). The geographical range of Laetmonice pro- ductor is enormous. Some forms burrow in the mud, a process in which the spines seem to be instrumental. This habit accounts for the fact that the setae and elytra of certain species are commonly found coated with mud. The aphroditids are sluggish in movement. They often occur as conmiensals and give support to a great variety of external parasites such as other annelids, pro- tozoans, sponges, coelenterates, ecliinoderms, bryozoans, crustaceans, and tuni- cates.^ Thus, in speaking of Laetmonice productor Mcintosh (Challenger AnneUda, 1885, p. 43) says: — "A large number of parasitic growths — sponges, Foraminifera, diatoms, hydroid zoophytes, Polyzoa, Loxosomae, ascidians, en- tangled worms, and others in tubes of sponge-spicules — occur amongst the bristles." All are carnivorous, and eat a great variety of animals, including other aphroditids and annelids in general. Key to Genera. a. Lateral tentacles as well as a median one present : Triceraiia Haswell. aa. With only a median tentacle. b. Eyes implanted on base of antenna; dorsal hairs not felted over the eljlra; no arrow-shaped setae; ventral setae with bifid tips Aphrogenin Kinberg. bb. Eyes not on base of antenna; dorsal hair more or less felted. c. Eyes pedunculate. d. Hairs of notopodiuin in part arrfiw-formed ; dorsal felting loose and often incomplete, e. Ncuropodial setae with the. tips bifid, distal region not pectinate. . . .Laetmonice Kinberg. dd. Notopodial setae simply serrate along convex side or smooth, but never arrow formed, long, prone, dense Ponlogcnia Claparede. cc. Eyes sessile; dorsal felting very dense, irregularly pierced by large brown hairs; parapodia with many fasciae of irised hairs Aphrodita Linn6. Aphrodita Linne. Linnd, Syst. nat., ed. 10, 1758, 1, p. 655; McIntosh, British annelids, 1900, 1, pt. 2, p. 241. Halithea Savigny, Descript. Egj-pte. Hist, nat., 1809 [= 1822], 1, pt. 3, p. 11, 18. Milnesia Quatrefages, Hist. nat. anneles, 1865, 1, p. 211 (min. ad part. M . horealis). Aphroditella Roule, Bull. Mus. hist, nat., 1898, 4, p. 191. ' For a detailed account of both external and internal parasites in the several groujis of Aphrodi- toicea see G. Darboux, Recherches sur les aphroditiens. Bull. sci. France & Belgique, 1900, 30, p. IS et seq. so THE ANNELIDA POLYCHAETA. Apheodita defendens, sp. nov.^ The prostomium is a little longer than wide, shortly inversely subpyriform, being widest in front. Convex above and in front. On dorsal surface toward anterior end are two slight rounded tubercles, but no eyes could be definitely discovered in the types; if present, they are colorless and obsolete. The median tentacle in the type is very short and clavate, apparently representing only the ceratophore; but in the paratype the style is present as a long slender filament nearly equalling the prostomium in length. The short basal segment of palpi narrow, less than half the width of prostomium; the main part widening from base to or beyond anterior edge of facial tubercle and then regularly tapering and distally becoming slender, seven times or more the length of the prostomium, bearing numerous distinct sensory papillae. The facial caruncle prominent, compressed laterally and running to an acute edge cephalad, the dorsal surface strongly roughened, somewhat tubercular. Peristomial parapodia laterally compressed, lying close against parapodium and proximal part of palps ; the parapodia proper surpassing the prostomium by less than one and a half the length of the latter. Tentacular cirri arising near distal end on ectal side, the dorsal stouter than the ventral. Setae of peristomial parapodia all capillary, in flat tufts. Lower lip an elongate lobe as usual, occupying middle region of II and III and pressing against IV; its sides incurved. Metastomial somites beneath a little convex laterally with greater part between nearly flat. Very clearly separated from each other by transverse folds and from the parapodia by the usual deep furrow. Surface densely crowded with papillae which are commonly even more dense and conspicuous on the parapodia. The elytra are large, widely overlapping and wholly covering the dorsal region of body and head. They are smooth, and rather thin but tough. The fimbriate organs rather small, widest at base, convexly narrowing distad, the edge with few, well-separated but blunt processes. Neuropodia of middle region about one third, or a Uttle less, the width of the somites. Neurocirrus of typical parapodium arising in usual position from a low elevation or transverse ridge; short, slenderly subulate, just attaining bases of ventral series of setae, no sub terminal knot. The notocirri long and slender filaments ordinarily passing through and lying upon the felt. They lack terminal and sub terminal enlargements. ' defendere, to ward off or defend. LAETMONICE. , 81 The dorsal felt is of uniform thickness, regular, tough and essentially smooth throughout. Neuropodial setae not concealed by the felt but much shorter than in A. echidna Mcintosh. They are all deep, almost blackish, brown in color, with the tips of some appearing paler. Arranged m the usual three series, of which the dorsal consists of two or occasionally of three, the middle mostly of five, and the ventral of eight to twelve spines, in the type mostly toward the upper limit, in the paratype, a much smaller specimen, toward the lower. The spines of the dorsal series are stout, distally somewhat compressed and longitudinally weakly sulcate down the middle of the flattened side, straight or shghtly curved distally. Setae of middle series much more slender, commonly less than a half or a third the diameter of the dorsals; evenly and obviously curved beyond middle, pointed. The ventrals much more slender than the medians, more strongly curved, commonly with a soft, flexible, pointed tip. No slender iridescent setae evident in the type, the lateral fibres all densely coated with foreign material. The notopodials in two series. In both the setae are in the form of stout straight spines, stouter than the dorsal neuro- podials, those of the upper series greatly so. The spines are all straight, pointed, and erect, rising distally free from the felt or often almost wholly concealed. In each series usually three in number, of which one may be reduced in size. Thirty-seven somites in type. Length, about 40 mm. Width to tips of setae 30 mm.; to bases of para- podia ventrally, 16 mm. Locality. Off Aguja Point, Peru, 20 m. N. W. : Sta. 4654 (lat. 5° 46' S., long. 81° 31' 9" W.). Depth 1,036 fms. Bottom, dark brown mud. Bottom temp. 37.3° F. 12 November, 1904. One specimen. Laetmonice Kinberg. Ofvers. K. vet. akad. Forh., 1855, 12, p. 382; Malmgren, Ofvers. K. vet. akad. Forh., 1865, 22, p. 53; ibid., 1867, 24, p. 129, Levinsen, Ofvers. Nordiske Annulata, 1883, pt. 2, p. 26; Roule, Bull. Mus. hist, nat., 1898, 4, p. 191. Laetmaionice Kinberg, Fregatt. Eugenies Resa. Zool. Annulater, 1857, p. 7; Baird, Jourii. Linn. soc. London. Zool., 1865, 8, p. 179; Quatrefages, Hist. nat. annelfe, 1865, 1, p. 199; Ehlehs, Mem. M. C. Z., 1887, p. 44; Daeboux, Bull. sci. France & Belgique, 1900, 30, p. 102; McIntosh, Brit, annelids, 1900, 1, pt. 2, p. 258. Laetnionicella Roule, Bull. Mus. hist, nat., 1898, 4, p. 191. 82 THE ANNELIDA POLYCHAETA. Laetmonice "wtvillei (Mcintosh). Laetmonice producta var. wyvilUi McIntosh, Challenger Annelida, 1885, p. 44, pi. 7, fig. 3, pi. 4A., f. 9-11. Laetmonice producta wyi'illei Treadwell, Bull. U. S. fish comm., 1906, 1903, 23, pt. 3, p. 1157; Moore, Proc. Acad. nat. sci. Philad., 1910, p. 386. Plate 11, fig. 1, 2. Locality. Off Peru: Sta. 4675 (lat. 12° 54' S., long. 78° 33' W.). Depth 3,120 fms. 22 November, 1904. Four specimens. These specimens agree in general with the form described by Mcintosh. They show the same papUlose ventral surface, and the very dark, dull, coarse dorsal setae. The dorsal setae agree well in structure with those of the types excepting that the tip is perhaps proportionately a little more slender. There are three or four recurved teeth on each side but in one of the spines there are proximad of these principal teeth a series of reduced ones on each side such as noted also in certain spines of the typical L. benthaliana Mcintosh. The ventral setae are nearly typical, excepting that the terminal hook seems longer, approaching more the condition in L. producta Grube; the pinnae are very numerous, seventy or more in number, and the basal hook is small and short as in the types. The ventral cirri differ in being minute, more as is typical for benthaliana. The precise relationship of the forms grouped under and about producta has yet satisfactorily to be worked out when sufficient material becomes available. Laetmonice benthaliana (Mcintosh). Laetmonice producta var. benthaliana McIntosh, Challenger Annelida, 1885, p. 45, pi. 8, fig. 4, 5, pi. 4A, fig. 12, pi. 5A, fig. 1, 2. Laetmonice producta benlhaliana Moore, Proc. Acad. nat. sci. Philad. , 1903, p. 420; Izuka, Journ. Coll. sci. Imper. univ. Tokyo, 1912, 30, p. 84, pi. 9, fig. 7-10. Localities. Off Panama: Sta. 4458 (lat. 6° 30' N., long. 81° 44' W.). Depth 555 fms. Bottom, green sand. Bottom temp. 40.2° F. 24 February, 1891. Two specimens. Off the Galapagos Islands: Sta. 3402 (lat. 0° 57' 30" S., long. 89° 3' 30" W.). Depth 421 fms. Bottom rock and Globigerina ooze. Bottom temp. 42.3° F. 28 March, 1891. Between Panama and the Galapagos Islands: Sta. 4630 (lat. 6° 45' N., long. 81° 42' 30" W.). Depth 556 fms. Bottom green sand. Bottom temp. 40.5° F. 3 November, 1904. Four specimens. PONTOGENIA CURVA. 83 These specimens agree in general appearance and structure with the descrip- tion of the typical examples. The ventral setae are typical excepting that the tip is somewhat less strongly hooked. The dorsal setae also agree excepting that the curvature mentioned as evident in certain views does not appear clearly in these specimens. The ventral cirri seem to be larger than in the types as they are easily seen with the naked eye. This is a widely distributed form, having been recorded from the region of Kerguelen and from south of Australia as well as from the North Pacific. It has a large bathymetrical range, having been taken in Suruga Bay at a depth of only 26 fms. (Albatross), and in the North Pacific (lat. 35° 22' N., long. 169° 53' E.) at the great depth of 2,900 fms. (Challenger). Laetmonice sp. A single specimen of a form which has been at some time dry, is in poor condition for satisfactory study. Locality. Off the Galapagos Islands: Sta. 3400 (lat. 0° 36' S., long. 86° 46' W.). Depth 1,322 fms. Bottom light grey Globigerina ooze. Bottom temp. 36.1° F. Exped. 1891. PoNTOGENiA Claparcde. Annflidcs Chi'top. Golfe Naples, 1868, p. 57; Grube, Jahresb. Schlesch. gesellsch., 1875, p. 68; Annu- lata Semperiana, 1878, p. 19; Ehlers, Mem. M. C. Z. 1887, 15, p. 46; Dabboux, Bull. sci. France & Belgique, 1900, 30, p. 102. PONTOGENIA CTJRVA, Sp. nOV. Plate 10, fig. 2-7; Plate 11, fig. 12. The body in general outline is oblong, with the caudal end much narrowed as usual and the anterior end more broadly rounded. Evidently there is con- siderable deformation through the specimens having been at one time dry. The precise number of' somites could not be determined, but there are near twenty-seven to thirty pairs of parapodia. The length of the type, exclusive of the setae, is at present near 9.5 mm. and with the setae, 12.5 mm. The width to the bases of parapodia is 3.5 m.; to the tips of the parapodia is 6 mm.; and to the tips of the setae, 10 nun. The paratype is 8.3 mm. long, with the width of body proper 3.2 mm., to tips of parapodia, 7.25 mm., and to tips of setae, 11.5 mm. 84 THE ANNELIDA POLYCHAETA. The dorsum is matted with much entangled foreign matter which wholly conceals the surface, the foreign material including even fragments of coral in addition to the finer material. The ventral surface presents numerous minute tubercles or points. The parapodia are long and cylindroconical, the narrowing distad being very gradual. (Plate 10, fig. 8). The ventral setae are dark brown in color. They are long, projecting between two and three millimeters beyond the tip of the parapodia. The principal setae curve decidedly toward their distal ends. Each is distally bifurcate as in such forms as P. chrysocoma (Claparede) and P. sericoma Ehlers, though differing in detail of form. The principal branch is curved with its concavity toward the minor branch or tooth and in a direction opposite to the principal cm-vature of the seta. The lesser tooth is straight and projects at a wide angle. The most ventral in the series are much more slender than the most dorsal ones. In addition to these there are in some of the more anterior neuropodia numerous much finer setae. These are paler in color. They vary much in stoutness among themselves in each fascicle. They may be curved much as those of the principal type above described; but instead of a single subapical tooth they present a series of small teeth below a naked tip. The series of teeth may be short, much as in the ventral setae prevaihng throughout in P. maggiae Augener, except that the teeth in that form are fewer and shorter; but more commonly a series of teeth may extend on both sides of the setae to the middle or below, or the series on one side may be longer than on the other. Thus these setae are typically bipectinate. (Plate 10, fig. 3-7; Plate 11, fig. 2). The dorsal setae are arranged as usual and are numerous and conspicuous. They vary in length, the shorter ones curving close to the dorsum and by their uncinate tips aiding the finer dorsal hairs in holding much foreign material. The setae in general increase much in length caudally, some of those on the posterior somites being ten milUmeters in length. They all widen from the base distad to the middle region and then narrow into a long, slenderly acuminate, distal region which is apically conspicuously curved or uncinate. Each seta appears more or less flattened and grooved along one side. The edges are wholly smooth. The dorsal hairs are fine and smooth. Locality. Gulf of Mexico: Sta. 2370 (lat. 29° 18' 15" N., long. 85° 32' W.). Depth 25 fms. Bottom of coarse gray sand and broken shell. 7 Febru- ary, 1885. Two specimens. The specimens had unfortunately been at some time dry, the hardening ACOETIDAE. 85 deforming them and rendering a complete description impossible. However, as the setae furnish clearly distinctive characteristics, it has seemed advisable to describe and figure the species. Pontogenia sericoma Ehlers, also occurring in the Gulf of Mexico, is at once to be distinguished from the present species by its characteristically straight and strongly serrate dorsal setae; P. maggiae Augener, taken in the Carribean off Montserrat, is also conspicuously different in the pre- vailing form of its ventral setae as well as in the dorsal setae. ACOETIDAE. The members of this family have the body elongate, moderately flattened dorsoventrally, and composed of numerous somites. The prostomimn is without a facial tubercle. Eyes either all sessile or two of them borne on conspicuous peduncles or ommatophores. Tentacles three, two, one or none. Palpi present, long and subulate. Parapodia biramous. Elytra occurring on somites II, IV, V, VII and there- after alternately with the notocirri. With setae either all simple (Acoetinae) or in part composite (Peisidicinae) . Proboscis at the end with a crown of numerous marginal papillae. Always armed wath four horny jaws. The acoetids are normally tubicolous. For special cases see, e.g., Watson, Observations on the tube-forming habits of Panthalis oerstedi, Trans. Liverpool biol. soc, 1895, p. 9; Ehlers, Mem. M. C. Z., 1887, 15, p. 56, under his ac- count of Euarche tubifex {Ewpanthalis kinbergi Mcintosh) . They are carnivor- ous and the most voracious of the aphroditoids. Key to Genera. a. Composite setae present Peisidiciiwe. b. No dorsal cirri, somites not numerous Peisidice Johnson. 6b. Dorsal cirri present; somites numerous Haswellia Darboux. aa. With no composite setae Acoetinae. b. Tentacles present. c. With but two tentacles. Two ommatophores, branchiae present Eupolyodonies Buchanan. cc. With three tentacles. d. Two eyes borne on ommatophores. e. With branchiae; first pair of parapodia normal Acoetes Milne Edwards. ee. No branchiae; first parapodia modified Panthalis Kinberg. dd. Eyes sessile, two or four in number Eupanthalis Mcintosh. 66. No tentacles; eyes sessile Restio Moore. 86 THE ANNELIDA POLYCHAETA. Synonymy of Genera. Acoetes Milne Edwards is the same as the older Polyodontes Renier, but the latter name, being preoccupied, is not available. Eupompe Kinberg is also synonymous with Acoetes. Euarche Ehlers is a synonym of Eupanthahs Mcintosh. Panthalis Kinberg. Ofvers. K. vet. akad. Forh., 1865, no. 4, p. 386; McIntosh, British annelids, 1900, 1, pt. 2, p. 400. Acoetes Dabboux, Bull. sci. France & Belgique, 1900, 30, p. 117 (in part). Panthalis panamensis, sp. nov. Plate 11, fig. 4-8; Plate 2, fig. 1-6. The posterior end of the type is missing. The part present has sixty somites caudad of the peristomium. It is, exclusive of the protruded proboscis, 30 mm. long with a maximum width, over all, of 6 mm. The maximum width is about 6 mm. from the anterior end. From that level the body narrows cephalad and more slightly caudad. The general color is a light brown with the parapodia yellowish; darker anteriorly but with no distinct markings at present detectable. The prostomium is divided into two halves as usual; each half presents a distally much enlarged ommatophore, the half as a whole being clavately thick- ened proximad and distad from the narrow base of the ommatophore, but with the proximal region, or prostomial lobe proper, considerably the larger. Ommat- ophore and prostomium proper about equal in length. At its distal end each ommatophore bears a conspicuous eye. It is darkened two thirds the distance to its base. At the base of each ommatophore above there is a small but con- spicuous, black, sessile eye. The median tentacle arises in the usual position between the prostomial lobes; it narrows slightly distad to a level below the apices of the ommatophores, where it narrows more abruptly to a slender tip which extends distally beyond the ommatophores. The lateral tentacles are similar in form and length. Each has a pigmented area proximally. The palpi are long and acuminate, in the present contracted condition in the type being two and a half to three times as long as the prostomium and ommato- phores. The ceratophores of the cirri of the peristomial parapodia are distally on a PANTHALIS PANAMENSIS. 87 level with the narrowest region of the ommatophores where attached to the lobe bearing the sessile eye. The cirri have the same shape as the median tentacle and are of nearly the same length ; each has a dark pigmented patch proximally . No setae were detected on the parapodia of the peristomiima. The elytra have the usual arrangement, occurring on II, IV, V, VII, etc. Anteriorly they meet and overlap along the median line, but elsewhere they leave the middorsum naked between the two rows. The elytra are thin, delicate and transparent. In outhne they are very broadly elUptic or nearly circular. Each is weakly campanulate, being depressed somewhat in funnel-form at place of attachment and with the border showing a tendency to turn up over all or part of its circumference. The margin is free from ciha and the surface is smooth. (Plate 12, fig. 5, 6). The dorsal cirri are stout at base and strongly acuminate distad, subulate. They extend beyond the distal end of the parapodia but are clearly surpassed by the setae. The ventral cirri are small conical processes attached near or somewhat proximad of the middle of the ventral surface of the parapodium. Each is very short and does not reach the end of its parapodium. The para- podia are conspicuously flattened anteroposteriorly; very deep at base, being there about as deep as long, narrowing subconicaUy distad; the rami very short and scarcely separated, blunt, of about equal extent. Acicula two in each parapodium. Pale in color, darker distally than proxi- mally. Stout at base, strongly acuminate distad but with tip not finely acute; with numerous longitudinal fibrillae and distally usually showing many cross striae. The middle setae are stout spines somewhat clavately enlarged and flattened. Distally they are a little curved and end in a short, acute point below which on one side is a series of fine teeth and on the opposite side a long, lash- like process which in most cases in the type has been broken off close to its base. Of the teeth there are ten to sixteen in each series. (Plate 12, fig. 3, 4). The setae of the dorsal series vary much in thickness and length, some being exceedingly fine and capillary, others much coarser, though all are much more slender than those of the middle series. The principal ones much exceed in length those of the middle series. Each presents a long, slender shaft which has distally a lance-like or fusiform enlargement prolonged into a long, very slender, acute tip which is more or less curved. This tip is fringed along both sides, the hairs extending proximad farther on the convex side than on the concave, while distally the hairs increase in length and form a brush-like structure (bi- pinnate, penicillate) . In some of the finer setae the hair-like processes of the 88 THE ANNELIDA POLYCHAETA. tip are sparse and widely separated. (Plate 1 1, fig. 7, 8) . The setae of the ventral series are, as usual, much more slender than those of the middle series and are mostly also decidedly longer. Each toward the distal end has a fusiform enlargement at which there is an abrupt bend or crook. Above the enlarge- ment is a long, slender, acutely pointed tip. On each side of the head is a series of coarse scales which are well separated; above the enlargement these scales are succeeded by fine hairs which are very densely crowded. (Plate 12, fig. 2). The setae of the first setigerous somite are conspicuously different from the forms above described. The dorsal setae are exceedingly fine, long, and finely pointed; the surface of these appears in part minutely obscurely roughened. The setae of the median series are slender and elongate; each is expanded into a narrow blade near the middle of its length and is distally drawn out into a long, slender, acuminate and curved tip, the seta as a whole also curving; on the convex side from the base of the expanded blade distad is a close series of processes giving the edge a finely serrate or pectinate appearance. (Plate 12, fig. 1). The setae of the ventral series are of the same general form as those of the other parapodia ; but scales occur only along one side and are uniform to the distal end excepting for reduction in size. They are smaller in size. The dorsal and ventral setae of the second setigerous somite are hke those of the first; but those of the median series are conspicuously different, being of the general form described as typical above but lacking the subapical process or spur. (Plate 11, fig. 5, 6). The extended proboscis is strictly cylindrical. It is 6 mm. long and about 3.2 mm. in thickness. In the dorsal series of papillae at its distal end five on each side of the longer conically acuminate median one. The papillae of the ventral side are the same in number and arrangement. (Plate 11, fig. 4). The maxillae are slender and long with the two upper ones not differing, or differing but Mttle, in size from the inferior ones. In the type the superior maxillae each closes to the left of the corresponding ventral one. The paratype is badly preserved. It is incomplete posteriorly. Exclusive of the proboscis it is 75 mm. long and consists of about ninety-two somites. The posterior half of the body is more strongly narrowed in comparison with the anterior. Locality. Panama. Shore. 20 March, 1900. Two specimens. This species belongs with those having two pairs of eyes, a sessile one in addition to the stalked pair, the latter alone being present in P. oerstedi, the typical species. It has resemblances to the Japanese P. jagasimae Izuka. From that species it differs, e.g., in the form of the proboscis and in the smaller SIGALIONIDAE. 89 number and different form and proportions of its papillae, and especially in the detailed structure of the setae of the different series. SiGALIONIDAE. The body is most commonly long and narrow, cyhndrical and vermiform, or, more rarely, short and somewhat flattened as is particularly the case in Eulepi- dinae. The prostomium is rounded. The eyes may be four, two or none. When present all are sessile. The tentacles in number are three, two or only one. The palpi, always present, are long and attenuated distad, smooth throughout. The lateral tentacles in most genera are fused, excepting at their tips, with the first parapodia which are carried well forward. Parapodia bii-amous. Notopodia bearing simple setae. The neuropodia may also bear only simple setae (EulepicUnae) , but more commonly (Sigalioninae) bear composite setae either exclusively or mixed with simple setae. Elytra borne on somites II, IV, V, VII and on the alternate succeeding somites caudad to the twenty third or, less commonly, to the twenty seventh, after which both cirri (cirriform branchiae) and elytra occur on all somites aUke. The proboscis ends in a marginal crown of papillae and is armed with four horny jaws. The members of this family occur from the httoral region down to depths of several hundred fathoms. They often occur buried in mud or sand some centimeters below the surface. Key to Genera. a. All setae simple; body short and somewhat flattened Eulepethinae, nom. nov. b. Elytra on somites II, IV, V, VII etc Eulepethus, nom. nov. 66. Elytra on somites II, III, IV, VI, VII etc Pareulepis Darboux. aa. The setae in part composite; body usually long and slender, cylindrical, less commonly short. Sigalioninae. b. With no median tentacle; lateral tentacles small, attached at anterior end of proboscis; branchiae well developed Sigalion Cuvier. 66. A median tentacle present; branchiae well developed or not. c. Tentacle one, the laterals absent. d. Dorsal cirri or branchiae none; no setae on the first somite Pholoe Johnston. dd. Branchiae present but rudimentary; setae on the first somite Eupholoe Mcintosh. cc. Tentacles three; branchiae well developed. d. Lateral tentacles free only at tips, fused proximally with parapodia of the first somite. e. Median tentacle long bearing on its ceratophore a pair of prominent spatulate ctenidia; elytra completely covering the dorsum. /. Composite setae falcigerous, distally sometimes flagelliform. 90 THE ANNELIDA POLYCHAETA. g. Terminal piece of composite setae, long, articulated Slhenelais Kinberg. gg. Terminal piece of composite setae very short, not articulated, apex entire. Sthenelanella Moore. ff. Composite setae spinigerous Sihenolepis Willey. ee. Median tentacle without ctenidia; elytra not completely covering the dorsum, the latter naked at middle anteriorly. /. Composite setae falcigerous; median tentacle typically attached at anterior margin of prostomium; elytra thick, with numerous papillae to which solidly adhere grains of sand or particles of shells, etc Psammolyce Kinberg. //. Composite setae spinigerous; median tentacle very short, inserted farther caudad directly on the prostomium; elytra thin and smooth, with no such adhesive papillae bearing foreign bodies Leanira Kinberg. dd. Lateral tentacles free, not fused to first parapodia; median tentacle small, inserted directly on prostomium above; composite setae falcigerous Euthalanessa Darboux. Synonymy of Genera. Thalanessa as used by Mcintosh, Haswell and various more recent writers is a quite different genus for which Darboux rightly proposes another name, Euthalanessa. Eusthenelais Mcintosh (1876) is regarded as synonymous with Sthenelais Kinberg, as I am able to find no generic differences. Conconia Sclmiarda is also equivalent to Sthenelais. Eulepis Grube is preoccupied in Insecta (Dalman, 1820) and also in Rep- tiUa (Fitzenger, 1843). It is here replaced by Eulepethus, nom. nov. and the name of the subfamily changed to Eulepethinae. Sthenolepis Willey. Ceylon pearl oyster fisheries report, 1905, pt. 4, p. 259. Sthenolepis areolata (Mcintosh). Willey, Ceylon pearl fisheries report, 1905, pt. 4, p. 259; Moore, Proc. Acad. nat. sci. Philad., 1910, p. .391; IzuKA, Journ. Coll. sci. Imper. univ. Tokyo, 1912, 30, p. 89, pi. 10, fig. 8. Leanira areolata McIntosh, Challenger Annelida, 1885, p. 151, pi. 21, fig. 3, pi. 25, fig. 8, 9, pi. 13A, fig. 1; MoOKE, Proc. Acad. nat. sci. Philad., 1903, p. 426. Locality. Off E. point Santa Rosa Island, Cal.: Sta. 4571 (lat. 33° 40' N., long. 119° 35' W.). Depth between 20 and 900 fathoms, a special sounding not taken. Character of bottom and bottom temp, not ascertained. 7 October, 1904. One incomplete specimen. The species was dredged by the Albatross earlier in the same year at sev- eral points near Monterey Bay and off the southern coast of California at depths from 66 to 971 fathoms. (C/. Moore, Proc. Acad. nat. sci. Philad., 1910, p. 391). POLYLEPIDIDAE. 91 SiGALioN Cuvier. Regne Animal, ed. 2, 1829, 3, p. 207; Audouin & Milne Edwards, Ann. sci. nat., 1832, ser. 1, 27, p. 398; Hist. nat. litt. France. Annelides, 1834, 2, p. 103, Kinberg ,(3fvers. K. vet. akad. Forh., 1865, no. 4, p. 387; D,uiBoux, Bull. sci. France & Bclgique, 1900, 30, p. 115; McIntosh, British annelids, 1900, pt. 2, p. 427. Thalanessa Baird, Journ. Linn. soc. London. ZooL, 1865, 8, p. 32. SiGALioN pouRTALESi Ehlers. Mem. M. C. Z., 1887, 15, p. 57. Locality. Gulf of Mexico: Sta. 2370 (lat. 29° 18' 15" N., long. 85° 32' W). Depth 25 fathoms. Bottom of coarse grey sand and broken shell. 7 February, 1885. One specimen. POLYLEPIDIDAE. Of the five famihes of truly elytra-bearing polychaetes which are here made to compose a superfamily Aphroditoidea, one (Polylepididae) is not represented in the collection of the Albatross. This is a small family embracing but two genera, each represented by a single imperfectly known species. They approach the Sigalionidae in having composite setae but are distinguished particularly in bearing elytra on all the somites. The prostomium bears a single tentacle and a pair of palpi. The proboscis is armed with four horny jaws. The two genera, as known from the original accounts, may be easily separated as follows. Key to Genera. a. With suctorial processes on dorsal and ventral surface of the parapoJia; setae all composite. Pdogcnia Schniarda. aa. With no such suctorial feet; notopodial setae simple, the neuropodials composite. Pohjlepis Grube. Synonymy of Genera. The second genus was designated Lepidopleurus by Claparcde (Annelides Chetop. Golfe Naples, 1868, p. 105) ; but as this name was previously used for a mollusc, Polylepis, adopted by Grube (Annulata Semperiana, 1878, p. 16) from Claparede's name for the family, may be used. Grube, however, from a study of a specimen in Claparede's collection which he believes to be that author's Lepidopleurus, doubts that this genus is in reality a member of this group as he found an alternation of elytra and cirri in the specimen (see Jahresber. 02 THE ANNELIDA POLYCHAETA. Schlesch. gesellsch., 1876, 53, p. 72). If a valid genus it would in such case probably belong in the Sigalionidae. The name of the present family would accordingly have to be changed to Pelogeniidae. Palmyridae. Probably near the Aphroditoidea are to be placed the two famiUes Palmy- ridae and Chrysopetalidae, neither of which is represented in the present col- lection. Their genera as at present known may be separated by means of the following keys. Key to Genera. a. Notocirri on somites I, II, III, IV, V and then on alternate somites to the end of body; basal portion of paleae short and straight; borders of palae smooth and rounded. . Palmyropsis Potts. aa. Notocirri on somites I, II (?), Ill, VI, and thereafter on alternate somites to near end of body; basal portion of paleae long; borders serrate Palmyra Savigny. The annehd listed by Mcintosh in the Challenger report as Palmyra aurifera Savigny and on which he found small elytra, is not that species but apparently is a true aphroditid near Pontogenia. Chrysopetalidae . Key to Genera. a. Body short, somites few. ' 6. Paleae covering the dorsum in large part. c. Some of the paleae broad, others narrow Paleanolus Schmarda. cc. Paleae equal Chrysopetalum Ehlers. 66. Paleae narrow, leaving most of the dorsum bare Dysponetus Levinsen. aa. Body elongate, somites numerous Bhawania Schmarda. Heteropale Johnson is a synonym of Paleanotus Schmarda. Nepthydidae. The body is elongate and composed of numerous somites. In cross-section somewhat tetragonal but with the dorsum convex and the venter typically flattened. Usually pale, pearl-gray with iridescence, only rarely well pigmented. Varying in size from one or two centimeters to twenty-five centimeters. Somites mostly less than one hundred and fifty. The prostomiimi is flattened and commonly subrhomboidal in outline as NEPTHYS. 93 seen from above, less commonly quadrangular or hexagonal. Normally there are fom* tentacles, two borne on the anterior margin on each side, or in rare cases, only two tentacles are present. Eyes two in number and small, or absent. Peristomial somite normally fused with the second one. Parapodia biramous, the branches widely separated from each other and each provided with a special membranous lobe or lamella more or less strongly developed; and in connection with it often other processes. In addition the notopodium bears a small notocirrus and a branclna, and the neuropodium bears a neurocirrus and may or may not bear also a branchia. Each branch of the parapodia bears a stout aciculum. The setae are all simple, or rarely composite setae may occur in the neuropodia. The setae are mostly strongly cross-striate or camerated, while some are serrated and some have lyriform tips. Anal cirri usually one, rarely two. Proboscis showing two regions; ^\ath or without two short horny jaws; a double row of bifid papillae around the aperture and with or rarely without papillae in longitudinal series (14-22). The members of this family are \agorous animals with a strong muscular development. They hve most abundantly in or near the Uttoral region though they areoccasionaUy taken from considerable depths {e.g. Nepthys phyllobranchia Mcintosh from 1,240 fathoms). They frequent sandy bottoms or sand more or less mixed with slime or mud in which they biuy themselves with sin-prising rapidity, using the proboscis in forming the burrow (Cf. Gravier, Nouv. arch. Mus. hist, nat., 1901, ser. 4, 3, p. 126). In their aUmentary tracts Gravier found such forms as diatoms, radiolarians, sponges, Foraminifera, and the remains of other polychaetes which their characteristically strong general mus- culature and their powerful probosces enable them to overcome. The family is remarkably homogeneous, only a single genus being recognized by most authors though various other groups have been proposed as indicated by the synonomy given below under Nepthys. Nepthys Cuvier. RIgne Anim., 1817, 13, p. 203; Savignt, Descript. Egypte. Hist, nat., 1809 [ = 1822], 1, pt. 3, Audouin & Milne Edwaeds, Hist. nat. litt. France. Ann61ides, 1834, 2, p. 232. Diplobranchus Quatrefages, Hist. nat. anneles, 1865, 1, p. 433. Portelia Quatrefages, Op. cit., 1865, 1, p. 431. Aglaophamus Kiptoerg, Ofvers. K. vet. akad. Forh., 1865, no. 4, p. 239. Aglaopheme Kinberg, Ihid., p. 240. 94 THE ANNELIDA POLYCHAETA. Nepthys ectopa, sp. nov.'' Plate 15, fig. 1-7. The general color is light brown without distinct markings excepting a short median longitudinal dark hue extending caudad on the dorsum from the caudal angle of the prostomium, and a dark band in the median ventral furrow which at the anterior end is Y-shaped. The type, which lacks the posterior region, is composed of forty-eight somites. It has a total length, exclusive of the proboscis, of near 27 mm. and a maximum width of 3 mm. The body is clearly widest at the anterior end (at the 5th or 6th somite), narrows strongly to about the twelfth somite, and then more gradually caudad. The prostomium is in the form of a broadly subtriangular plate with base cephalad, the apex of which extends back to the fourth somite and thus divides above the first three somites. The anterior margin is straight or very sUghtly concave between the widely separated lateral corners which bend back obliquely caudad. The anterior border slopes ventrocephalad. Surface in general smooth and shining. Close to each lateral margin and about midway of the length is a convex elevation, subelliptic in outline, which apparently represents an eye though wholly without dark pigment at present. On the anterior margin are two pairs of short, colorless and conical processes or tentacles; on each side there is one on the obhque line of the corner and one at the end of the straight median region close to the first one, the two on each side being thus widely separated from the two on the other. (Plate 15, fig. 1). What is interpreted as the peristomium appears on the ventral side as a straightly margined, narrow band weakly divided by a transverse furrow; it extends up each side and disappears beneath the border of the first setigerous somite before reaching the prostomium, which thus appears to be wholly free from it. It bears no cirri. The first two setigerous somites are evident only dorsally on each side of the prostomium. On e ach side these somites he between the prostomiima and the third setigerous somite, against wliich these outer ends lie. Each bears only a fully developed notopodium, the neuropodium being wholly absent. The fourth somite (thu-d setigerous) extends farther ventrad than the two preceding but is likewise incomplete beneath, while above it is partly separated ' eK7oiros, strange. NEPTHYS ECTOPA. 95 by the prostomium, the apex of which extends into it. It bears both notopodia and neuropodia. The succeeding somites are all complete and simple. They are separated above and laterally by deep intersegmental furrows; ventrally between the base of the neuropodia on each side and the prominent neural furrow, the intersegmental furrows are rather faint, becoming again more pro- nounced in this furrow. The ventral furrow widens out clavately toward the anterior end in the wider region of the body, the elevated part of the venter on each side curving ectad and dorsad. The furrow between the peristomium and the succeeding part of the venter is very deep, in strong contrast with the following intersegmental furrows which are weak. With the exception of the first two pairs, the parapodia are biramous. In each of the first two pairs the parapodium is represented by the notopodium alone, this having the essential form of those in the typical parapodia succeed- ing. Each is low, subcorneal, but with a broad top and bears a pointed, conical, somewhat flattened appendage on its ventral side at base. The parapodia (notopodia) of these first two pairs are situated much farther dorsad than the others, lying up close to the prostomium. The notopodium of each one of the third pair of parapodia is abruptly farther ventrad and about halfway from the second to the level of the foiu-th; from the fourth, the notopodia become gradually located farther and farther ventrad to about the tenth somite, after which the same level is maintained. In a typical parapodium the two branches are widely separated. (Plate 15, fig. 3). The notopodium is short and thick, with the distal end convex, obhque to the main axis, and bearing along its cir- cumferential hne the numerous setae excepting for a short open space or break on the dorsal side, while the top of the aciculiun touches the surface near the centre of this area and shows conspicuously in a small dark elevation; from the ventral side of the notopodium a conspicuous branchial lobe projects ventrad reaching the neuropodium; this lobe is thick at base but conspicuously flat- tened distally in the anteriocaudal direction and is also expanded distally, the distal end subtruncate with a tendency to be weakly bilobate from a small notch at middle, while slight crenulations may also show along the ventral edge. In the anterior region in going cephalad this lobe becomes smaller and smaller, at the same time becoming more pointed distad until of the conical form above mentioned on the most anterior ones. No notocirri are present in the type. The neuropodium of a typical parapodium of the middle region of the body is also short and thick with the upper side straight, the ventral more slanting; the distal surface is broad and convex and slopes obliquely ventromesad; 96 THE ANNELIDA POLYCHAETA. it is encii-cled by setae, as in the case of the notopodium, excepting for a break on the ventral side, while the aciculum is situated at the centre; the neuro- podiiun bears near its base on the ventral side a short, subcyhndric, distally acuminate cirrus. In each notopodium and neuropodixma there is a single stout, dark reddish aciculum occupying a central position with its acute tip extending into a slight conical elevation at the surface. The aciculum is obviously longitudinally fibrillate and may show a cross-striation or cross-wrinkling, particularly in the distal region as shown in the figure. (Plate 15, fig. 7). The setae are arranged on each notopodium and neuropodium in a hne that has the form of an elongate ellipse which is commonly narrowly broken at the dorsal end in the notopodia and at the ventral in the neuropodia. The setae are all simple and none of the crochet-type occur. The setae on the anterior side in each case are much finer than the others and are very flexible; each ends in a fine acute tip below which it is covered until toward the base by nmnerous, closely arranged, trans- verse, toothed ridges or pectinae. (Plate 15, fig. 4). The principal setae are much coarser; each from a stout base narrows continuously distad, the tip being fine, acute, and smooth, while proximad of the tip the seta along one edge is closely set with very fine teeth or hairs. These setae appear on the average to be coarser in the neuropodimn than in the notopodium. (Plate 15, fig. 5, 6). They are densely fibrillate and tln-ough wear often are much frayed distally, the breaks occurring naturally in the direction of the fibrillae which may at the end become separated Uke hairs and give a brush-Uke appearance. No specially modified setae on particular parapodia were detected, though the much rubbed condition of some prevented complete study. The proboscis is fully protruded in the type. It has a length of 3 mm. and a maximimi diameter equal to this. Just within the distal margin and about the opening is a closely arranged series of long papUlae each of which is distally bifid with each lobe conical, the two lobes in each case lying in the same vertical or radial plane ; the papillae at each side are shorter than the dorsal and ventral ones. Along the distal margin and immediately proximad of it are arranged five encirchng series of slenderly conical, well-separated papillae; these decrease in length from those of the most distal to those of the most ventral series which are very small. In the type the papillae form twenty-one radial series. The re- maining median and proximal region of the proboscis is wholly smooth. (Plate 15, fig. 2). Locality. Off Aguja Point, Peru, 20 m. N. W.: Sta. 4654 (lat. 5° 46' S., PHYLLODOCIDAE. 97 long. 81° 31' 9" W.). Depth 1,036 fathoms. Bottom dark brown mud. Bot- tom temp. 37.3° F. 12 November, 1904. One specimen. Nepthys sp. A fragment of a specimen belonging to this genus was dredged from a depth of 39 fathoms off the Coast of Mexico (Sta. 3418). Expedition, 1891. It lacks both ends. Phyllodocidae. A large family in which the body, while usually more or less elongate and vermiform and either cylindrical or depressed, varies enormously in size, with the number of somites from comparatively few (e. g. twenty-three) to eight hundred or more. The prostomium is of various forms, bluntly subconical to suboval. With four tentacles and often in addition with an unpaired median tentacle normally posterior in position. Palpi none. Eyes two or four, usually small but larger in the epitokous forms, rarely absent (Paralacydonia). Tentacular cirri from one to four paks (or possibly five in Kinbergia) borne on from the first one to the first three somites, or none (Paralacydonia). Nuchal organ from strongly developed to none. Nephridia with inner end always closed, in connection with numerous solenocytes. The genital funnel distinct though often at maturity opening into the nephridial canal. Aside from the phyllodocoids, the Glyceridae and the Nepthydidae alone present these conditions (see Goodrich, The nephridia of the Polycheta, Quart, journ. micros, sci., 1900, 43, p. 699). The parapodia in most cases uniramous with a single aciculum and one fascicle of setae; in other cases biramous and with two acicula. Certain forms in the epitokous phase acquiring natatory simple setae as in the syllids. Neu- rocirri and notocirri flattened, thin and foUaceous, and all containing strongly developed mucus-glands. The cirri in the aberrant Paralacydonia, however, vary from this normal type. Setae in most cases composite, but sometimes in part simple and very rarely (Nans) all simple. Certain epitokous forms acquiring special, simple, long, nata- tory setae. Pygidium with two anal cirri which are either subulate or foliaceous. Proboscis commonly powerful, bipartite, and smooth, or bearing variously 98 THE ANNELIDA POLYCHAETA. arranged papillae, rarely with small chitinous pieces but never with true jaws. The phyllodocids proper are mostly essentially Uttoral animals occurring in and near the tidal zone under stones, on the mussel beds, on rock or in fissures in the same, in the laminarian region and similar places. In some regions they are particularly abimdant at moderate depths of from eight to twelve fathoms on bottoms covered by shells bored or disintegrated by Clione, (see Gravier, Recherches sxu* les phyllodociens, Bull, scient., 1896, 29, p. 305). The Chal- lenger secured a specimen from the considerable depth of five hundred fathoms which Mcintosh identifies as Genetyllis oculata. The phyllodocids are very active, not only moving about freely over solid surfaces but also swimming with ease and grace, an activity in which the expanded foUaceous cirri play an im- portant role. Some forms, too, are normally pelagic, such as particularly the species of Pelagobia, Lopadorrhynchus, Prolopadorhynchus, Pedinosoma, Maupasia, and Haliplanes and also the two new genera Nans and Mastigethus. These forms are included by Reibisch (Die pelag. phyllodociden u. typhloscoleciden, Ergebn. Atlant. Ocean * * * Plankton exped., 2, N. c, p. 18) in Claparede's subfamily group Lopadorhynchidae (properly Lopadorrhynchinae) against which he places a subfamily Phyllodocidae (Phyllodocinae) sens, str., which groups at present seem artificial. The pelagic genera mentioned embrace species color- less and transparent and for the most part small, most not exceeding 10 mm. in length, though some may rarely reach 40 mma. Most are less than 5 nam. long. Unlike the pelagic alciopids these forms do not show a special increase in the size of the eyes, these being, on the contrary, reduced or absent; but in possible com- pensation the tentacular cirri are often especially strongly developed. The setae for the most part are exceptionally fine and long. The epitokous forms of certain species of which the atokous forms are littoral are pelagic and show corresponding adaptive modifications. The females of these pelagic epitokous forms approach the shore to lay their eggs, these being deposited on Algae, stones, etc. The pelagic forms are ordinarily colorless, while the httoral forms are among the most brilliantly and variously colored of annelids; and it is note- worthy that the colors of those from deeper waters are of the same character. The phyllodocids are boldly carnivorous. Gravier (op. ciL, 1896, p. 306) notes having found in their alimentary tracts the setae and other debris of various other annelids, including terebeUids, spionids, sabellariids, syllids, and others, in addition to those of their own kind, which they attack and rend by Pim^LODOCIDAE. 99 means of their probosces. He found in the digestive tube of Eulalia viridis (Linne) another individual of the same species ahnost intact; and St. Joseph made a similar observation in the case of Eulalia pallida Claparede. They often attack forms larger than themselves. Rarely vegetable fragments, as of Fucus, and diatoms are found in their alimentary tracts. Gregarines occur frequently in the alimentary tract of phyllodocids. A number of external parasites have been noted by St. Joseph and others, e. g. colonies of Vorticella on Anaitides mucosa (Oersted), the orthonectid Rhopalura pterocirri on Sige (Pterocirrus Claparede) macroceros, a crustacean, Herpyllobius articus, on Eulalia pallida, etc. In this work the groupings and general system elaborated by Bergstrora in his recent revision (Zui* systematik der polychaetenfamilie der phyllodociden, Zool. bidrag, 1914, 3, p. 37) have been in general adopted. Key to the Subfamilies and Genera. a. No composite setae present Natinae, subfam. nov. Setae of two distinct types; two pairs of tentacular cirri both belonging to the first somite; notocirri of first ordinary somite strongly developed Nans, gen. nov. aa. Composite setae present. b. Eyes present; notocirri of the normal foliaccous type; tentacular cirri present. c. Notocirrus of first normal somite reduced; tentacular cirri either two pairs, both on the first somite, or three pairs with one on the first and two on the second somite Etconinae. d. With three pairs of tentacular cirri; ventral tentacular cirri of second somite foliaceous. Pseudomy slides Bergstrom. dd. With but two pairs of tentacular cirri; all tentacular cirri filiform. e. The peristomium bearing distinct setigerous parapodia; pelagic forms. . . .Pelagobia Greef. ee. Peristomium without setae or parapodial processes proper; non- pelagic or creeping forms. /. First normal somite with setigerous parapodia. g. Proboscis distally with two lateral rows of true papillae and also bearing chitinous denticles Mysta Malmgren. gg. Proboscis smooth with neither true papillae nor denticles Eteone Savigny. //. First normal somite only with ventral cirri, parapodia proper and setae wholly lacking. Hypereteone Bergstrom. cc. Notocirrus of first normal somite fully developed. d. With only two pairs of tentacular cirri, one on the first and one on the second somite which latter bears also an ordinary ventral cirrus Lugiinae. Lugia Quatrefages. dd. With more than two pairs of tentacular cirri, or rarely with but two pairs, in which case the second somite bears no neurocirrus. e. Three pairs of tentacular cirri or but two, of which only one pair occurs on somite I. /. Tentacular cirri occurring on but two somites and either three pairs with the two pairs on the second somite, or else but two pairs with ventral cirri of second somite absent or rudimentary Mystidinae. g. With three pairs of tentacular cirri, fully developed, two pairs pertaining to the second somite; prostomium free Mystides Thcel. gg. With only two pairs of developed tentacular cirri, or a rudimentary third pair may be present (ventrals). h. All setae composite; prostomium fused with the first soniite . Pedinosoma Reibisisch. hh. Simple as well as composite setae present. i. Prostomium fused only with the first somite. 100 THE ANNELIDA POLYCHAETA. j. Neurocirri present on the anterior somites bearing only simple setae. Prolopadorhynchiis Bergstrom. jj. Neurocirri not present on these somites. A;. Proboscis without papillae; without prominent nuchal processes. Lopadorrhynchus Grube. kk. Proboscis on each side with a long, finger-like papilla; on each side of pro- stomium a large branched nuchal process prominently extended. Mastigethus, gen. nov. a. Prostomium fused with the first normal somite as well as with the preceding; neurocirri on all somites Reibischia Bergstrom. dd. Tentacular cirri occurring on three somites, one pair on each Protomystidinae. Protomystides Czerniavsky. ee. Either four pairs of tentacular cirri or but three, in the latter case two pairs on the first somite Phyllodocinae. f. With four pairs of tentacular cirri. g. All somites bearing tentacular cirri wholly free. h. All parapodia with two acicula. i. All somites bearing tentacular cirri fully developed. . . . Austrophyllum Bergstrom. a. First somite dorsally reduced. j. Ventral cirrus of second segment fohaceous and asymmetrical. Hesperophyllum Chamberlin. jj. Ventral cirrus not fohaceous and asymmetrical Notophyllum Oersted. hh. All normal parapodia with a single aciculum. i. All somites bearing tentacular cirri fully developed; a median tentacle present. j. All tentacular cirri filiform or fusiform; proboscis distally diffusely papillose. Eulalia Savigny. jj. Tentacular cirri not all filiform or fusiform, ventrals of II modified. k. Ventral tentacular cirri of second somite thick, asymmetrical, the others fili- form or fusiform; proboscis smooth Natalia Bergstrom. kk. Ventral tentacular cirri of second somite thin, foliaceous, asymmetrical; the entire proboscis diffusely papillose Steggoa Bergstrom. ii. First tentaculo-cirriferous somite dorsally reduced. j. An unpaired tentacle present. k. Proboscis smooth; all tentacular cirri filiform or fusiform. Eumida Malmgren. kk. The entire proboscis papillose. I. Tentacular cirri filiform or fusiform Pirakia Bergstrom. U. The ventral tentacular cirri of somite II thin and foliaceous, asymmetrical. Sige Malmgren. jj. No unpaired tentacle but with a nuchal papilla. k. All tentacular cirri filiform or fusiform. I. Proboscis proximally with papillae in series Anaitides Czerniawsky. U. Proboscis proximally with papillae diffuse PhyUodoce Savigny. kk. Only the dorsal tentacular cirri of second somite filiform, the others short, thick, and almost globular Sphaerodoce Bergstrom'. gg. Not all somites bearing tentacular cirri free. h. Prostomium free, but the first two somites fused with each other. i. The tentaculo-cirriferous somites fully developed, forming dorsally a collar-like sweUing; proboscis with two lateral rows of large papillae. .Paranaitis Southern. ii. Tentaculo cirriferous somites dorsally strongly reduced; proboscis diffusely papil- lose. j. All tentacular cirri flask-shaped Genetyllis Malmgren. jj. Tentacular cirri of I and the ventrals of II filiform, the others flattened, fohaceous Nereiphylla Blainville. hh. Prostomium fused with one or more of the succeeding somites. 1 Bergstrom {op. cit., 1914, p. 87) first mentions this genus with its type-speoies (PhyUodoce quadra- ticeps) under the name Globidoce; but on subsequent pages, and in the diagnoses, Sphaerodoce is used. The occurrence of Globidoce in the text was undoubtedly an oversight. PHYLLODOCIDAE. 101 i. Prostomium fused with the first somite only HijpoeuMia Bergstrom. u. Prostomium fused with two or all three of the somites bearing tentacular cirri. j. Prostomium fused with the first two somites Prochaetoparia Bergstrom. jj. Prostomium fased with all three somites bearing tentacular cirri, the resulting part bearing simple setae Chaeloparia Malmgren. ff. With three pairs of tentacular cirri. g. Somites bearing tentacular cirri wholly free Haliplanes ReibLsch. gg. First somite completely fused with the prostomium Maupasia Viguier. 66 . Eyes none; tentacular cirri none; notocirri small, not truly foliaceous. Paralaajdoniinae subfam. nov. Paralacijdonia Fauvel. Synonymy of Genera. Eracia Grube is a synonym of Eulalea Savigny. Porroa Quatrefages is a synonym of Eteone Savigny, as is also Eteonella Mcintosh. PterocLrrus Claparede is identical with Sige Grube, both having the same species as the type, Pterocirrus macroceros = Sige fusigera, macroceros being the older. Mesomystides Czerniavsky is a synonym of Mystides Theel. Trachelophyllmn Levinsen has been withdrawn into Notophyllum Oersted, its type, T. luikeni Levinsen being the same species as the type of Notophyllum, N. foliosum (M. Sars). Macrophyllum Schmarda is very probably a synonym of Notophyllum Oersted, but as the type of the typical species (M. splendens) no longer exists, and the species is known only from the original accoimt, the position of the genus is somewhat doubtful. The same is true of Myriacyclum Grube, based upon Notophyllum myria- cyclum Schmarda. Until this species is again found it will probably be impossible correctly to place it. The types of the two species included by Quatrefages ia his genus Kin- bergia are also lost and the species {Phyllodoce macropthalma Grube and P. longidrris Grube) have not been identified recently. Five pairs of tentac- ular cirri are ascribed to members of this genus; but Bergstrom's suggestion that Grube enumerated as the first of these nuchal organs unusually strongly extruded seems plausible. Eunomia Risso (1826), regarded by its author as near Phyllodoce, is doubtful even as to family. No types of its two species {E. tympana and E. viridissima) exist. The genus should probably be discarded. Nothis Pruvot (1885) is similarly unrecognizable. Protocarobia and Paracarobia were established by Czerniawsky (1882) as 102 THE ANNELIDA POLYCHAETA. subgenera of Carobia to which he gives an individual definition and scope, with Phyllodoce tenuissima Grube and Anaitis lineata Claparede as the types. The first of these species is synonymous with Phyllodice macrolepidota Schmarda, and Protocarobia is here accordingly regarded as a synonym of Phyllodoce. The position of Paracarobia must remain somewhat doubtful until A. lineata has been restudied. Eulahdes Czerniawsky has as its type Eulalia saxicola Quatrefages, a prob- able synonym of E. bilineata Johnston, the genotype of Hypoeulalia. In this case Eulalides must take precedence over Hypoeulalia. Czerniawsky's genera Mesoeulalia (type, E. incompleta Quatrefages, from Torres Strait) and Paraeulalia (type, Phyllodoce (Eulalia) multicirrus Grube, from the Philippines) require a restudy of the type-species before they can be properly placed or estimated. The type of the same author's Pseudonotophyllum is Notophyllmn poly- noides Oersted, which is a synonym of Phyllodoce foliosa Sars, the type of Noto- phyllmn. Pseudonotophyllum is thus completely and permanently in synonymy. That author's Eunotophyllum, with Notophyllum alatum Langerhans as type, is probably also to be merged with the same genus. Anaitis Mahngren (1865) was preceded by .\naitis Desponchel (Lepidop- tera, 1844). Hence Paranaitis was supplied by Southern in 1914. Anaitides Czerniawsky. Bull. Soc. imper. nat. Moscou, 1882, 57, p. 158; Bergstrom, Zool. bidrag., 1914, 3, p. 108, 118, 138. The better known species of this genus may be separated as follows. Key to Species. a. Proboscis normally with a median dorsal row of five papillae in addition to twelve lateral of nine or ten papillae each; styles of neurocirri of middle region narrow, drawn out to a point distally. A. palagonica Kinberg. aa. With no median dorsal row of papillae on the proboscis. b. With eight lateral rows of papillae on the proboscis; the dorsal cirri of the first three normal somites as wide as long A. citrina (Malmgren). bb. With twelve lateral rows of papillae on the proboscis; the dorsal cirri of the first three normal somites longer than wide, c. Proboscis with not more than twelve papillae in each of the middle lateral rows. d. Proboscis with nine or ten papillae in each lateral row. e. Ventral cirri of middle region of body with styles drawn out into a narrowly acute tip; dorsal cirri of this region with lamellae subquadrate. /. Tliird normal notocirrus broadly eUiptic; three first pairs of normal notocirri much smaller than the succeeding ones A.heterodrrus Chamberlin. ANAITIDES LAMELLIFERA. 103 SJ. Third normal notocirrus strongly narrowed dislad, ovate; first three pairs of notocirri not abruptly much smaller A. mucosa (Oersted). ee. Ventral cirri of middle region of body with apex of styles not acutely prolonged, short and rather obtuse; styles of dorsal cirri not subquadrate. /. Prostomium narrowed conically and subacutcly forward, only moderately incised behind, as wide as or wider than long A. lamellifera (Pallas). ff. Prostomium broadly rounded in front, not conically narrowed, and at least a little longer than wide, very deeply incised behind A. sancti josephi (Gravier). dd. Proboscis with at most seven or eight papillae in each middle lateral row. e. Styles of neurocirri of middle region of body distinctly pointed; styles of notocirri of same region drawn out to a point, not quadrate A. nculata (Ehlers). ee. Styles of neurocirri of middle region of body short and broad, distally blunt; dorsal cirri of this region quadrate, not distally prolonged A. maculala (Linnc). cc. Proboscis with twelve or more papillae in each middle lateral row. d. Twelve or thirteen papillae in each middle lateral row; styles of neurocirri of middle region surpassing the neuropodia, and the free part of setae exceeding the latter in length. A. groerilamlica (Oersted). dd. Number of papillae in each middle lateral row at least eighteen; styles of neurocirri of middle region not attaining end of neuropodia, and the latter always longer than the free part of setae A. compsa, sp. nov. Anaitides lamellifera (Pallas). Nereis lamdlifera Pallas, Nova acta Petrop., 1788, 2, p. 232, pi. 5, fig. 11-17. Nereis lamelligera Gmelin, Syst. nat. ed. 13, 1791, 1, p. 6, 3128. Phyllodoce lamelligera Johnston, Ann. nat. hist., 1840, ser. 1, 4, p. 225, pi. 6, fig. 1-6 (in part); Ehlehs, Borstenwiirmer, 1864, p. 139; Johnston, Cat. annelids Brit, mus., 1865, p. 175; Fischli, Abh. Senck. naturf. gesellsch. Frankfurt-a-M., 1900, 26, p. 120; McIntosh, British annelids, 1908, 2, pt. 1, p. 76 (in part) ; Izuka, Journ. Coll. sci. Imper. univ. Tokyo, 1912, 30, p. 195 (in part) ; Fauvel, Result, campag. sci. Prince Monaco, 1914, 46, p. 111. Locality. Panama: Perico Island. Shore. Exped. 1904-05. One speci- men. The single specimen referred to this species is very small, only about 20 mm. long exclusive of the protruded proboscis. It seems to have been broken and is regenerating posteriorly; the regenerating piece is sharply set off from the preceding portion. The number of somites remaining in front of the regenerat- ing region is nearly sixty-eight. The color is light brown, lacking the conspicu- ous coloration and markings present in typical large specimens as appears to be the usual condition in dwarf specimens. The rows of papillae at the base of the proboscis are six on each side as usual; these show a tendency to be irregular and are not in all cases distinctly separated from each other. There are at the apex of the proboscis eighteen large papillae encircUng the opening. The cirri are as usual or very nearly so. It is evident that two or more distinct species have been confused by vari- ous writers imder the name lamelligera, some of the specimens listed under it being true members of Phyllodoce in the restricted sense, while others are clearly 104 THE ANNELIDA POLYCHAETA. members of Anaitides. The figures given by Pallas show that his species was, in part at least, a true Anaitides. Phyllodoce laminosa Savigny, is not an Anaitides. Mcintosh erroneously makes this a synonym of the lamellifera of Pallas, the lamelligera of Gmelin. In the Pacific A . lamellifera proper has pre- viously been recorded from the Moluccas (Fischli, supra) and from Japan (Izuka). Anaitides patagonica (Kinberg). Carohia patagonica Kinberg, Ofvers. K. vet. akad. Forh., 1865, no. 4, p. 242. Phyllodoce (Anatis?) sanctae viceiUis McIntosh, Challenger Annelida, 1885, p. 166, pi. 27, fig. 9, pi. 32, fig. 8, pi. 14A, fig. 14, 15; Theadwell, Bull. U. S. fish comm., 1906, 1903, 23, pt. 3, p. 1158. Phyllodoce (Anaitis) madeiriensis Langerhan.';, Zeitschr. wiss. zooL, 1880, 33, p. 307, pi. 17, fig. 44a, 44b; Ehleks, Nach.K. gesellsch. wiss. Gottingon. Math. phys. klasse, 1897, p. 25. Phyllodoce madeiriensis Ehlers, Abhandl. K. gesellsch. wiss. Gottingen. Math. phys. klasse, 1901, p. 72. WiLLEY, Rept. voyage Southern Cross. Polychaeta,1902, p. 270; Ehlers, Deutsche Siidpolar exped., 1913, 13. Zool., 6, p. 453; Fauvel, R&ult. campag. sci. Prince Monaco, 1914, 46, p. Ill, pi. 6, fig. 5-13. Anaitides patagonica Bergstrom, Zool. bidrag, 1914, 3, p. 147. Locality. Off Peru: Sta. 4653 (lat. 5° 47' S., long. 81° 24' W.). Depth 536 fms. Bottom dark brown volcanic mud. Bottom temp. 41.3° F. 12 November, 1904. One incomplete specimen. The fragment consists of the anterior end. Exclusive of the fully protruded proboscis it is about eight nulhmeters long with a width, exclusive of the para- podia, of 1.2 mm. and over all of 3.5 mm. The extruded proboscis is 3.8 mm. long. There are forty somites present. Bergstrcm {loc. cit.) states that he has found only sixteen or eighteen papillae in the crown about the opening of the proboscis ; but in the present specimen the nimiber is seventeen, the same as given by Ehlers (op. cit., 1897, p. 28) for his South Georgian specimens. Treadwell gives sixteen for his Hawaiian speci- mens. Bergstrom finds only five papillae in the middorsal series and never more than nine or ten in each lateral series, and considers higher counts than this due to confusion between series resulting from contraction in preservation. The present specimen, however, fully substantiates WUley who found larger num- bers. In the middorsal series there are nine papiUae of which the two most prox- imal and the one most distal are smaller. In the lateral rows the number varies from ten to twelve. The tentacles do not show the proximal annulation men- tioned by Langerhans and Ehlers, this being due, most likely, to preservation. It is possible that the species is here too broadly conceived; but in the evi- dence available I find no good grounds for a division. This appears to be the ANAITIDES COMPSA. 105 second record, of the species from the Pacific Ocean, the other locality being off the Hawaiian Islands. It was previously recorded also from the Madeiras, from Patagonia, Juan Fernandez, Falkland Islands, Victoria Land and other far southern points. Anaitides COMPSA, sp. nov.^ Plate 16, fig. 8, 9; Plate 16, fig. 1-6. This is a large and showy species. Inclusive of the parapodia it appears broad, though the body proper is rather slender. It increases in width to about the eightieth somite after which it narrows gradually and continuously to the caudal end. The total length of the type is 175 mm. The greatest width, exclusive of the parapodia, is 4.2 mm., and inclusive of parapodia, 10.4 mm. The nmnber of somites is nearly thi'ee hundred and forty-five. The prostomium is decidedly flattened dorsoventrally in front and thickens caudad. In outline it is broadly subcordate, wider than long, with the greatest width to the length about as 32:27. Laterally and anteriorly widely rounded, in front projecting a little beyond the tentacles or in some nearly on a level with these. A distinct transverse sulcus between the eyes. Eyes small, circu- lar, situated at one third the length of the prostomium from its caudal border, each being about one fourth the width of the prostomiiun from the lateral edge and thus about one half the \vidth apart. The tentacles are short, stout, and conical, the dorsal ones about one fourth the greatest width of the prostomium and the ventral ones a little longer. At each side the tentacles proximally are almost contiguous and project ectad or a httle cephalad of ectad. The tentacles of each side are widely separated from those of the opposite one. The first three somites are free from the prostomiimi and from each other, the first incomplete dorsally. The tentacular ckri of the first somite reaching to the seventh somite. The dorsal tentacular cirri of the second somite reach- ing to the fifteenth somite and the ventrals to the seventh. The tentacular cirri of the third, or first setigerous, somite reacliing to somite XIV. The somites in general are very short and closely crowded, in the widest region of the body of the type being between six and seven times as wide as long. Throughout most of the body the somites are dorsaUy weakly widely convex, the convexity being stronger in the anterior region. There is no mid- ^^KoiJL. 1(11. The specimens have the usual sixteen parapodia-bearing somites. A repre- sentative specimen is 21.5 mm. long and has a maximum width, exclusive of the parapodia, of 4 nam. The body increases in length to the tenth parapo- diferous somite, and then more gradually narrows caudad from the thirteenth or fourteenth somite. The dorsum is moderately arched. HESIONE GENETTA. 187 The general color is an iridescent grey of slight yellowish cast. The dorsum of each segment is characteristically marked with dots of deep violet color. The dots on the first segment ordinarily are numerous and closely arranged or confluent in a transverse band across the caudal half. On the other seg- ments there is a triangular patch on each side between the dorsal sulcus and the parapodium, the point of the area being ventrad and a little above base of para- podiimi. On each somite between the sulci the dots are nearly absent from the anterior half, or with but a few scattered ones present, but form a continuous series across the middle in which the median one is often largest, while in the posterior part the dots tend to leave the series open at the middle and to be largest at the lateral ends. The number of series of dots on each somite is ordinarily thi-ee or four, not including the scattered ones present in the anterior region of some. In one small specimen on each somite there is but a single spot on each side above the parapodium and thi'ee transversely elongate marks on the dorsum, or these may practically unite into a single transverse stripe. In the smallest specimens there is a solid stripe across the first segment in place of the band of segregated spots of the larger ones. Also on succeediiig somites there is but a single series of marks. The marks tend to fade out on the pos- terior somites. The venter in all is wholly without dark marks. Parapodia subcylindrical, distally truncate. The neui'ocirri usually extend near or a little beyond the tips of the setae. The notocu'ri are long, clearly exceeding the width of the body and the longer ones equal in length to the longest dorsal tentacular cirri, which extend back to the middle of the sixth parapodia- bearing somite. The anal cirri in length about equal to the longer tentacular cirri. The prostomium is much narrower than the succeeding somite, strongly narrowed forward, triangular in outline, with the apex rounded and the sides more or less bulging in such way that the caudal portion may appear subquad- rate, the narrowed anterior portion depressed. In the smaller specimens the prostomium appears more subquadi'ate ; with two short, moderately acuminate tentacles, one arising on each side from a slight notch a little caudad of the anterior end. The caudal margin of prostomium may be distinctly notched. A median longitudinal fiurow extends forward from this notch to a distinct , transverse, arcuate sulcus extending between the two posterior eyes and with its convexity forwards, and continues to a second transverse sulcus between or a little in front of the anterior eyes. From the latter transverse sulcus two sulci run forwards and are connected so as to form a small subquadrate area and then 188 THE ANNELIDA POLYCHAETA. continue, each bending out to the base of the corresponding tentacle. The anterior eyes are much larger than the posterior and are much farther apart. All eyes distinct. The setae, as in several other species of the genus, are of a distinctly green- ish color excepting the transparent distal piece. The tip of the distal piece presents the usual tooth below the apex. The subapical tooth proportionately stout, nearer the apex than usual, the lamina not extending beyond the apex of the lateral tooth. (Plate 22, fig. 7, 8). Localities. Paumotu Archipelago: Fakarava. 12 October, 1899. Three specimens. Paumotu Archipelago: Makemo. Reef flat. 20, 21 October, 1899. Two specimens. These specimens agree in general with the description by Grube of speci- mens from Samoa and the Philippines. They seem to be somewhat different, however, in the form of the prostomium and the character of the furrows on its dorsal surface. But the form of the prostomium appears dissimilar in the different specimens and according to age, and especially with sUght variation in orientation when studied. Grube's description is not sufficiently exhaustive, however, to remove all doubt as to the identity of the species. Hesione panamena, sp. nov. Plate 22, fig. 9, 10. The body consists of nineteen somites, of which sixteen bear parapodia. The length of the type is 40 mm. and its greatest width between bases of para- podia is 6.6 mm., this being at the tenth somite. The dorsum is much less arched than in H. splendida Savigny, and also, to judge from descriptions, than in the closely related H. reticulata Marenzeller, and the body appears propor- tionately broader. Dorsum, excepting the lateral cushions, marked with numerous, cinnamon- colored, longitudinal lines which are interrupted. Anteriorly and as far caudad as the middle is a median dorsal Une of this color somewhat heavier than the others and on each side of tliis are five, or at places incompletely six, broken Unes, the color-pattern being thus very like that in splendida and in the Philippine form described by Grube as intertexta. The distinctly bisulcate venter is, laterad of each sulcus, a dilute cinnamon color of a vague rosy tint. Between the sulci the venter is lighter, obscure yeUow, excepting in some parts immedi- HESIONE PANAMENA. 189 ately adjacent to the sulci. The lateral cushion-like region and the parapodia are paler and also vnih the vague rosy tint excepting the parapodia. The setae are green as in various related species, excepting the distal blades which are nearly colorless. The prostomium wider than long ; sides strongly convex; convexly elevated above, and ^\ith a short median longitudinal sulcus at the caudal end which bifurcates anteriorly. Eyes of the anterior pair decidedly larger and farther apart than those of the posterior pair. Antennae broken off in the type. The peristomium dorsally very short and finely longitudinally wrinkled, while ventrally much longer than usual. The usual eight pairs of tentacular cirri present, of which the dorsal are longer; the second dorsal reaches nearly to the fifth parapodrferous somite. Parapodia proximally subcyUndrical, distally conical, with the end tnincate. The eighth parapodiimi is 1.5 mm. long, this being about the same length as the setae, or the latter but little shorter. The ventral cirri normally extend a little beyond the distal tips of the setae. The dorsal cirri are long, and apparently entire, one of the posterior region exceeding in length the distance between the tips of the setae of the two parapodia of the same somite, though most of the setae present are shorter than this. The anal cirri are of about the same length. The setae are of the prevaihng general type. The subapical tooth is small, often rounded, and inserted above the middle of the distance between attach- ment of the covering lamella and the tip of the seta. The lamella extends much distad of the tooth, opposite which it is excavated ; it is nearly straight excepting sometimes at its tip, and the space between it and the seta proper is always narrow and sUt-Uke. (Plate 22, fig. 9, 10). The proboscis is not extruded in the type. Locality. Panama. Shore. 12 March, 1891. One specimen. This form in general structure and appearance is near H. splendida Savigny. Augener (Fauna Slidw.-Austr. Polych., 1, 1913, 4, p. 187) gives a wide scope to splendida. I beheve he includes two or more definitely separable specific forms mider that name. Not to mention other differences, an exami- nation of the setae of specimens of H. splendida (sicula Claparede) from the Mediterranean shows constant differences from those of H. panamena, the subapical tooth being decidedly longer and the lamella shorter and not passing beyond the tooth (Plate 22, fig. 11, 12). The figm'es given by St. Joseph (Ann. sci. nat., 1897, ser. 8, 5, pi. 19, fig. 136) and by Mcintosh (Challenger Annehda, 1885, p. 185, pi. 15A, fig. 10) for this species (under the name of 190 THE ANNELIDA POLYCHAETA. H. pantherina) as found on the coasts of France and at the Cape Verde Islands respectively, agree with my Mediterranean specinaens in this regard, so that I think the character must be regarded as constant. Marenzeller's figure of the seta (Sudjapan. Anneliden, 1879, pi. 3, f. 4) of his H. reticulata {Cf. Plate 22, fig. 13) shows a form different from that of the real H. splendida, as I believe, and that species seems therefore valid. The figures given by Gravier (Nouv. arch. Mus. hist. nat. 1900, ser. 4, 2, p. 175, 177, fig. 43-45) of the seta of his H. ehlersi {Cf. Plate 22, fig. 14) also represent a clearly different form, and I think the species will be found to be vahd in spite of an error as to a principal character upon which the separation was originally based. Leocrates Kinberg. Ofvers. K. vet. akad. Forh., 1865, no. 4, p. 244; McInto.su, British annelids, 1908, 2, pt. 1, p. 130. Lamprophaes GnunE, Jahresb. Schlcs. gesellseh., 1866, 44, p. 65. Tyrrhena CLAPAnfeDE, Annelidcs Chctop. Golfe Naples, 1868, p. 227. Dalhousia McIntosh, Challenger Annelida, 1885, p. 186. Leocrates iris (Grube). Lamprophaes iris Gritbe, Annulata Semperiana, 1878, p. 105; Jahresb. Schles. gesellseh., 1866, 44, p. 65. Locality. Society Islands: Papeete. Shore. 9 November, 1899. One specimen. The species is also known to occur in the Samoan and Philippine regions. Leocrates anomalus, sp. nov.^ The body is strongly fusiform and somewhat more narrowed caudad than cephalad. It is widest in the region of the eighth and ninth somites. The somites are shortest at the ends of the body. No dividing lines between somites are indicated on the dorsal sm-face. Length 17 mm.; greatest width of body proper, 3.25 mm. The original color rather uncertain. At present the type is of a pearly yellowish grey color, with the dorsum somewhat dusky caudally and laterally and without markings. The venter with a pale median line, bordered on each side by a dark line. The prostomium in the type somewhat shrunken, appearing subquadrate ' 'I'unaXos, anomalous. NEREIDAE. 191 or even a little wider in front of the anterior eyes than at base. Notched above in the median line at base and longitudinally furrowed in front of the notch, with a sulcus bending out toward each anterior eye and a quadrate figure in front of this outlined by sulci. The unpaired tentacle inserted in the caudal region, as usual, and lying in the median fiurow. On each side there are the bases of eight tentacular cu-ri, all having been broken off so that their lengths cannot be determined; but the bases of the upper ones are much the stoutest, and of these the second from the most pos- terior is thickest and the most anterior one smallest. First three parapodia with only neuropodium and neuropodial setae. Those succeeding have, in addition, a notopodium which appears as a tubercle on the dorsal side at the base of the neuropodium, this bearing finer, simple capillary setae in contrast with the usual compound setae of the neuropodium. The cirri are all broken off near the base. The bases of the first four pairs of noto- cin'i are conspicuously thicker than those following and of these the cirri of the first pair are stoutest, being of nearly the same thickness as the largest of the tentacular cirri. Each neui'opodium bears an acutely pointed, auriculiform process at its distal end above or dorsocephalad. Most notopodia are narrowed to a point ventrad of the setae. All setae in the type are colorless and transparent, or nearly so, or in part show a vague and very dilute greenish yellow cast. The capillary setae in the posterior segments are numerous, the notopodial fascicles being large and con- spicuous and extending beyond the distal end of the neuropodia. The tips of all the neuropodial setae are missing so that their structure could not be determined. The proboscis, unlike that of other species recorded from the Indo-Pacific region, presents near its distal rim, when extended, a half circle of conspicuous, chitinized, rounded papillae, these forming a half-crown across the dorsal half of the proboscis with none on the ventral half. The papillae are ten in number. Locality. Marshall Islands. A single specimen came up on anchor from a depth of 12 fms. Albatross Exped. 1899-1900. This form is characterized chiefly by the half-crown of chitinous papillae at the end of the proboscis, a character seeming at once to separate it from the preceding and from other species of the region. Nereid AE. This is one of the most homogeneous and clearly defined families of the Polychaeta, the characteristic and obvious structural appearance ordinarily 192 THE ANNELIDA POLYCHAETA. making possible their easy recognition. The body is elongated and cylindrical, or but moderately depressed. The somites are numerous and in the ordinary or atokous stage all are similar, excepting the usual modifications in the terminal ones. The prostomium is distinct and well formed. It bears two pairs of eyes, or these may rarely be absent. There is one pair of tentacles, and a pair of palpi which are characteristically massive and two-jointed, with the terminal joint short. The peristomium bears two pairs of tentacular cirri and may rarely bear parapodia and setae also. The parapodia in general are biramous, though the most anterior one or two pairs may be uniramous and the most posterior ones may be modified from the prevailing type. The notopodium is occasionally rudimentary (Namaner- eis and Lycastoides) . Notocirri and neurocirri present. The setae are composite and occur in two forms as to the character of the articulation, namely the unsynunetrical, or heterogomph, and the symmetrical, or homogomph, tjrpes. Usually both kinds occur at the same time, but not always, one type in some forms prevailing exclusively. Stout spines, or crochets, rarely present (Uncinereis, gen. nov.). The nephridia consist of long, convoluted tubules, each of which ends internally in an open ciliated funnel, or nephrostome. The pygidium in general bears two anal cirri. The proboscis in extrusion presents two distinct regions or rings, a distal, or maxillary, ring and a basal one. Each of these is again more or less clearly divisible into six areas, three dorsal and three ventral, which are indicated in descriptions as follows: — the median dorsal maxillary area is I, each lateral dorsal maxillary area II ; the corresponding ventral areas of the maxillary ring, III and IV respectively; the corresponding areas on the basal ring above are V and VI, and below VII and VIII. The proboscis always bears distally a pair of maxillae curved toward each other and dentate on the mesal edge. The surface of the proboscis otherwise may be smooth, or it may bear upon all or part of the areas small, soft or hard papillae, or teeth, the paragnatha, which are of much significance in classification. Wliile some species of nereids reproduce without changing their ordinary asexual body-form, many more undergo a pronounced metamorphosis affecting both the external and the internal structm'e at the time of sexual maturity and at the same time assume a pelagic life. The epitokous form, in general, is NEREID AE. 193 spoken of as the " heteronereis " stage. Heteronereis was erected as a genus by Oersted (Annulatorum Danicorum conspectus, 1843, p. 19) for epitokous forms of Nereis under the assumption that they were independent of any other known forms. In the metamorphosis into the heteronereis form the eyes increase in size, often to a marked degree, the prostomium may become indistinguishable though sometimes becoming otherwise modified, and the palpi commonly undergo a more or less pronounced reduction. At the same time the body becomes marked off into two regions differing strongly in the appearance of the parapodia of the two parts. Of these the anterior, or so-called nereid division, which is comparatively short, retains parapodia of the ordinary form, while the posterior or heteronereid division has parapodia conspicuously modified. These com- monly bear special foliaceous lobes and numerous, large, special, natatory setae. The sexual products arise in the posterior division where they may remain, giving it a darker and more opaque appearance contrasting with the commonly colorless and often transparent anterior region, or the products in other cases crowd forward into all the somites. Between the epitokous male and female a sexual dimorphism exists which is often very striking. Differences between the two forms are noticeable, particularly in the tentacles, palpi, and cirri, and sometimes in the prostomium (C/. Platynereis polyscalma, sp. nov. p. 219). The genus Eunereis of Malmgren, which has proved valid, was based upon the . epitokous form of E. longissima Johnston ; and Naumachius Kinberg and Hedyle Malmgren were apparently based upon the epitokous forms of species of Pseudo- nereis. The real relationship of the heteronereis was first established by Malm- gren (Zeitschr. wiss. zool., 1869, 19, p. 466) in Nereis pelagica. One and the same species may exhibit both a smaller, active, pelagic epitokous form and a larger, sedentary heteronereis which remains in a tube on the bottom, as has been well estabhshed e.g., in Nereis dumerili (Cf. Westinghausen, Mitth. Zool. stat. Neapel, 1891, 10; Mesnil and Caullery, Ann. Univ. Lyon, 1898, p. 146, ff.). It may also happen that a species may at one time reach sexual maturity without undergoing any metamorphosis, while at other times in passing into the epitokous stage it undergoes the change into the heteronereis. Viviparity, as an occasional but probably not necessary phenomenon, has been established for some species, such as the hermaphroditic (proterandrous) Nereis diversicolor. The nereids are essentially Uttoral animals, occurring mostly between the tide-marks or at but moderate depths, though sometimes found down as deep as 1,525 fms. {e.g., Nereis longisetis). They commonly construct tubes in the fissures in rocks or under stones, in the mud in the eel-grass stretches, and in 194 THE ANNELIDA POLYCHAETA. sponges or the stalks of decaying sea-weeds. They are not infrequent in the coralline and laminarian regions. As a rule they rapidly reform their com- monly thin, transparent and often collapsible tubes when released in an aquarium. While most nereids are strictly marine, some may live in brackish and even in fresh water, such being the case with most of the species of Namanereis (com- monly designated Lycastis) . A species of the closely related genus Lycastoides, L. alticola Johnson, was found in a fresh water stream of southern Cahfornia at an altitude 7,000 feet above sea-level (Cf. Ehlers, Nach. K. gesselsch. wiss. Gottingen. Math. phys. klasse, 1897, p. 70; Gravier, Bull. Soc. hist. nat. Autun, 1901, 14, p. 29; Johnson, Mark anniversary vol., 1903, p. 210). Some forms are commensal, such as Nereis fucata and others which live with the hermit- crab in shells of Buccinum, etc. {Cf. Mcintosh, British annelids, 1910, 2, pt. 1, p. 259; Harrington, Trans. N. Y. acad. sci., 1898, 16, p. 214). Some nereids live largely upon Algae, such being the case with Nereis cul- trifera Grube and A'^. pelagica Linne. In addition the members of the family feed upon small ova, sponges, Crustacea, and also upon other anneUds. Key to Genera. a. Tentacles arising from a very long common basal article inserted anteromesally on the prostomium. (Pelagic form) Kainonereis, gen. nov. aa. Tentacles with no such common basal article. 6. Proboscis with no paragnatha. c. Nereids with dendritic branchiae Dendronereis Peters. cc. With no dendritic branchiae. d. Noto)5odium rudimentary. e. Prostomium anteriorly deeply incised; tentacular cirri on each side arising from an elon- gate common basal article Lycastoides Johnson. ce. Prostomium anteriorly not thus deeply incised; tentacular cirri not arising on each side from a long common basal article Nainanereis, gen. nov.' dd. Notopodium well developed. e. Peristomiuni with parapodia and setae Micronereis Claparede. ee. Peristomiuni witliout parapodia or setae Lepionereis Kinberg. &6. Proboscis with paragnatha. c. Paragnatha all soft (papillae). d. Setae of two lands; eyes none Chaunorhynchus, nom. nov.^ dd. Setae all of one kind, homogomphs; four eyes present Tylonereis Fauvel. cc. Hard, chitinous or callous paragnatha present. d. Paragnatha all simply hard or callous TyUcirhyiichus Grube. dd. Horny or chitinous paragnatha present. e. Both chitinous and soft paragnatha present Leonnaies Kinberg. ee. Paragnatha all chitinous. /. Paragnatha conical, all separated from each other. g. Paragnatha occurring on both rings of the proboscis. ' vaiia, a stream or spring, in allusion to the occurrence of most species of this genus in fresh and brackish water. - Pro Ceratocephale or, as commonly, Ceratocephala, Malmgrcn, preoccupied in Crustacea, xawoj, gaping, flaccid, and piiyxos, snout. NEREIDAE. 195 h. Paragnatha present on all eight areas Neanthes Kinberg. hh. Paragnatha absent from one or more of the areas. ('. Groups I, II, and V lacking Cirronereis Ivinberg. M . Group V, or V and VI, lacking Nereis Linn6. gg. Paragnatha present on only one ring of the proboscis. /). Pre.sent only on the maxillary ring Ceratonereis Kinberg. hh. Present only on the basal ring Eunereis Malmgren. //. Paragnatha not all conical and at the same time well separated. g. Paragnatha all of one form, very small, and arranged in dense series or pcctinae. (Groups I, II, V, and sometimes VI, VII, and VIII lacking.) h. Stout crochets present in all but the most anterior notopodia in addition to the ordinary setae Uncinereis, gen. nov. hh. No crochets present. i. Group I lacking Piaenoe Kinberg. it. Groups I, II, V, and sometimes VI, VII, and VIII lacking. . Platynereis ICinberg. gg. Paragnatha of two or three forms, conical and transverse, or else these and in addition the pectinate type. h. Of two forms, conical and transverse, separated. i. All groups present Pcrmercis Ivinberg. a. Group V lacking Areta Kinberg. hh. Of three forms, conical, transverse, and pectinate Pseiidonereis Kinberg. Synonymy of Genera. Numerous other generic names have been proposed ; but nearly all of them must be included in those designated in the analysis above. Until their type- species shall have been restudied it must remain impossible satisfactorily to place Typhlonereis and PhyUonereis of Hansen and Nossis of Kinberg. Not a few species have been so inadequately described that it is now difficult or impos- sible to identify them generically. Unless some other characters than those presented by the proboscis and its armature shall be found it may become neces- sary still further to combine some of the genera recognized here, since variations in the arrangement and even in the form of the paragnatha are considerable in some species, particularly between smaller specimens and the fully grown ones (C/- Ehlers, Festsch. K. gesellsch. Gottingen, 1901, p. 112) discussion under Nereis variegata Grube which he identifies with Mastigonereis podocirra Schmarda, M. longicirra Schmarda, Paranereis elegans Kinberg, Nereis obscura Hansen, N. coerulea Hansen, N. micropthalma Hansen, A'^. stimpsonis Grube, A'', ferox Hansen and Naumachius pannosus (Grube) Kinberg. Since Ehlers, from a study of type-specimens and more abundant new material, finds pannosus of Grube, as identified by Kinberg and by him made the type of Naumachius, to be identical with elegans Kinberg, the type of Para- nereis, these two genera must be merged; and since they in turn cannot be kept distinct from Pseudonereis, all three must apparently be combined. Of these Pseudonereis has the priority. Naumacliius appears to have been based on the epitokous form. 196 THE ANNELIDA POLYCHAETA. Hedyle Malmgren was also based upon an epitokous form of a species of Perinereis. Included under Perinereis are also Malmgren's genera Lipephile and Stratonice. Nereilepas and Hediste have by some authors been so con- ceived as in part to cover this genus; but their types carry them to Nereis. Arete Kinberg is kept apart here tentatively but is quite likely also to have to be included; and Perinereis may in turn possibly have to be united with Pseudo- nereis. Leontis Malmgren and Iphinereis Malmgren (based on the epitokous stage) are the same as Platynereis Kinberg. Nicon Kinberg and Nicomedes Kinberg are sjTionymous with Leptonereis, the former also being preoccupied (Gray, Mammals, 1847). Alitta Kinberg is regarded as not differing generically from Neanthes Kinberg. Lycastis Savigny (Descript. Egypte. Hist, nat., 1809 [= 1822], 1, pt. 3, p. 45) was proposed for Nereis armillaris O. F. Miiller; but as this species proves to belong under Syllis in the Syllidae, the nereid generic group to which Lycastis has long been apphed remains without a name. To supply the lack Namanereis is proposed with N. quadraiiceps Gay as the type. Kainonereis, gen. nov.^ Prostomium short and narrow, narrowed cephaloventrad. Tentacle long, single, bifid at tip, varicose or annulated (male). Palpi reduced; biarticulate ; with proximal article stout, the distal more slender and soft. Fovu" eyes, large, the two of each side close together, the anterior more lateral in position, the posterior more dorsal and on caudal region of prostomium. Nuchal organs simple, ciliated pits. Peristomium with four pairs of tentacular cirri which are varicose or annu- lated (male). All parapodia biramous, each branch supported by a single, stout aciculum. Dorsal branch with two ligulae, the ventral with one. Setae all compound. Shafts strongly cross-striate. Neiu-opodial setae of anterior, or nereis region, falcate and setose. The notopodials in the anterior part of this region coarser and darker, with the distal piece short and distaUy blunt. Both dorsal and ventral cirri present. The notocirrus in anterior region expanded proximally and on some with the expanded region very large (fifth, sixth, and seventh pairs in type), forming elytra-like organs. Both notocirri and neurocirri in the ' KoivAs, unusual, and Nereis. KAINONEREIS ALATA. 197 heteronereis region with foliaceous expansions proximally. In this region also a special, additional foUaceous appendage at tip of the neuropodium and all setae replaced by the larger, paddle-shaped swimming setae. Anal cirri two ; annulated. Alimentary canal straight. Oesophagus with a pair of caeca. Genotype. — K. alata, sp. nov. This form is unquestionably very close to Nereis to which its precise rela- tionship can be decided only when the other phases of the type-species are known. It is given separate generic rank here chiefly because of the highly peculiar, long, single process bifm-cate at the tip and which may be morphologi- cally double or else may represent an extremely elongate anterior division of the prostomium, bearing at its tip the two short tentacles; and the elytriform de- velopments, possibly peculiar to the male, on three of the anterior pairs of para- podia, though special developments of parapodial structures are not infrequent in the family. One form of the anterior notopodial setae is quite special, but by itself would scarcely be regarded as of more than specific value. The reduction in size of the palpi is not infrequent in the males of Nereis. • Kainonereis alata, sp. nov.^ Plate 28, fig. 6-8; Plate 29, fig. 1-8. Epitokous or Heteronereis Phase. Body-waU colorless and transparent, but the body contents in part giving a brownish tinge. Appendages colorless. Setae colorless and transparent. The body is widest near the middle of the length, from where it narrows caudad to a point and cephalad to a much narrower anterior region consisting of five somites in front of the elytrophorous ones. These anterior somites narrow more gi-adually toward the cephalic region. A typical specimen, 10.5 mm. long, which seems to be about the average, consists of fifty-six somites. The prostomium is short and narrow, clearly deeper dorsoventrally than either the length or the width. The dorsal sm-face anteriorly between the anterior eyes is raised into a conspicuous, low, subcorneal, distally rounded ele- vation which bears at the top two small, transparent, secondary eminences or knobs. It may also be elevated at the posterior end above between the pos- terior eyes. The anterior svirface is incurved at about the middle height above, 'filatus, winged. 198 THE ANNELIDA POLYCHAETA. bulging out below this and extending into the long single tentacle. This ten- tacle seems to correspond to the usual paired tentacles since it is bifui'cate at the tip. The tentacle is a little less than three times as long as the prostomium is high. The bifm'cation at the tip is somewhat variable, but never exceeds one foiirth the total length. The tentacle increases in thickness proximad. It is distinctly annulated or jointed throughout its length, the joints short and num- erous. The palpi arise on the ventral sm-face immediately in front of the mouth and project a little caudad of ventrad. Each in length is about equal to the height of the prostomium and is conspicuously biarticulate, the proximal joint thicker and stouter, with sometimes faint signs of a secondary joint proximally. The distal joint is elliptic in outline, narrowly rounded distally. There are two pau's of eyes. Of these the posterior ones are dorsolateral in position, each occu- pying a caudolateral corner of the prostomium, with their axes directed ecto- dorsad. They are nearly circular in outline and are about their diameter apart. The anterior eyes are situated on the sides of the prostoiriium, each cephaloventrad of the corresponding posterior eye and with the axis directed ectad. They are decidedly smaller than the posterior ones and are less circular in outline, being broadly obovate to subelliptic. All eyes are very strongly convex. (Plate 28, fig. 6). The peristomium is decidedly longer than the prostomium and also clearly exceeds the second somite. It is wider than the prostomium and projects much below it. The border of the mouth is crossed radially by impressed lines or wrinkles. There are four pairs of tentacular cirri, all those of each side being attached close together between the eye and the mouth. The dorsal anterior cirrus is largest of the four. It is in length but Uttle longer than the tentacle and reached to the fourth somite or, in some, only to the third. The anterior ventral tentacular cirrus is much shorter ; but it is stouter and somewhat longer than the posterior ventral which, in tui'n, is longer than the posterior dorsal which seems normally to differ in being of more uniform diameter and blunt distally. The style of each cirrus is constricted at the base and attached tlirough the mediiun of a short, narrow cirrophore. The cirri are all annulate or varicose and all, except possibly the dorsal posterior ones, are conspicuously pointed distad. A small, simple nuchal pit occurs on each side back of the eye and close to the base of the upper posterior tentacular cirrus. (Plate 28, fig. 6). The succeeding or normal setigerous somites are all sharply separated from each other. The anterior four or five are particularly highly convexly arched above, and are also convexly but less strongly arched below. In the middle KAINONEREIS ALATA. 199 and posterior regions the arching is proportionately less strong. The second somite is two thirds as long as wide, essentially the same proportions being maintained also in the next five somites. The seventh somite widens from in front to the caudal end. The eighth somite is typically proportionately abruptly shorter, being but one half as long as wide, while the ninth is about two and a half times wider than long. The pygidium is small and bears two anal cirri. Each anal cirrus has a distinct, thicker cirrophore, upon which is borne the style. The style is short, when laid along the body reaching to the fom'th somite from the caudal end. It is moderately tapered distad and is constricted at the extreme base. It is strongly annulate like the other cirri. (Plate 28, fig. 7). The parapodia are attached laterally near the middle of the height. On the most anterior somites they are attached at the anterior end, but caudad they gradually shift to a middle position. The first eleven pah's of parapodia are contrasted with the others in being shorter and, in preserved specimens, at least, in projecting more directly ectad, the larger posterior ones projecting caudad of ectad, in not bearing foliaceous appendages on the neuropodia, and in their setae. The anterior parapodia differ in length among themselves, becom- ing progressively shorter in proceeding from the thirteenth forward to the first pair. All parapodia are biacicular and biramous, with each branch termi- nating in one or two special finger-like processes, and bear notocirri and neuro- cirri. In the short anterior parapodia the notopodium is a little reduced. Its two distal digitate processes are short and slender. One of these, the more dorsal, is in connection with the aciculum. The setae are few and of a special type. The neuropodium shows two short terminal processes, from one of which the setae arise and into which the aciculum extends without protruding through the surface; the second process is on the ventral side. The neurocirrus is attached on the ventral side at the very base; its cirrophore is thick and short; the style above its constricted base short and narrowly conical and not attain- ing the end of the neuropodimn. The notocirrus arises on the dorsal side near the middle of the length fi"om a very low elevation, or cirrophore; its style is narrow at the base, expanding at the middle into a small lamellar structure from one side of which a slender, pointed, finger-like process extends. (Plate 29, fig. 4) . The parapodia of the fifth, sixth, and seventh pairs are strikingly differentiated from the others in having the dorsal expansions on the notocirri greatly enlarged to form broad, subcircular elytra, the finger-like process itself being also much thicker than in the notocirri of other parapodia. (Plate 28, fig. 9 ; Plate 29, fig. 2) . In the notopodium several of the special stout setae appear, while the number of 200 THE ANNELIDA POLYCHAETA. the ordinary composite setae in the neuropodium increases. In the somites immediately following the seventh the elytra-like expansions of the notocirri are again lacking, but the notocirri undergo further progressive modifications, coming to appear as a thin membranous wing along the parapodium, with at the distal end a distinct, finger-like process, while the proximal end of the membrane is also free for a short distance ; the acicular process at the end of the notopodium and the other finger-like appendage become longer and about the same in size as the process on the neuropodium. The setae of these notopodia follo\ving the seventh are the same as those of the neuropodium, the special coarse setae being abruptly replaced. The neuropodia of the eighth, ninth, and eleventh parapodia remain nearly the same as in the more anterior ones. (Plate 29, fig. 3). In the twelfth the setigerous process bears at the distal end a thin, mem- branous, leaf-like process which on the thirteenth becomes much larger and narrowly subovate, with the distal end rounded. In the latter, too, the neuro- cirri have become proximally memb^'anous, with a slender, cylindrical, distal process, at one or both sides of the base of which is a low, rounded process often giving the neurocirrus the appearance of being doubled. (Plate 29, fig. 4). In the fourteenth and fifteenth parapodia the membranous appendage to the neuropodium has become still larger and reaches nearly to the ends of the shafts of the setae; it is very finely veined. The notocirral fringe becomes larger, the proximal end free as an angular, distally narrowly rounded lobe, while the distal process is more elongate; it hes commonly close against the large, non-acicular, notopodial process proximally. At the base of this finger-like, terminal noto- cirral process there are two, slight, rounded lobes on opposite sides. This is the typical form of parapodium prevailing throughout the remaining portion of the body. (Plate 29, fig. 5). In the caudal region the parapodia become reduced in size, but the same structures remain evident and retain the natatory setae throughout. The terminal neuropodial membrane is usually somewhat obliquely subtruncate across the distal end, with a small mucron at the middle. Two acicula in each parapodium, one in each branch. These are black and conspicuous, finely pointed distad, each extending into a special acicular process. The setae are all compound, but are of three distinct primary types. The noto- podial setae of the first seven pairs of parapodia are of a special type. (Plate 29, fig. 7). They are black or dark brown in color like the acicula. The shaft is gently doubly curved and terminates distally in a deep socket of homogomph form bent a little to one side. The shaft is strongly cross-striate throughout its length. The terminal piece is short and distally blunt or rounded, and a KAINONEREIS ALATA. 201 little notched on each side toward the base where the corresponding edge of the socket meets it, the piece being thus loosely clamped in place. Along one side it is closely, finely setose. In the most anterior parapodia these setae may not be above two in number, but the number increases to three or fouJr in the para- podia bearing the elytra. Behind these the dark special setae just described are replaced by setae like those of the neuropodia. (Plate 28, fig. 8). These are colorless and transparent and are clearly more slender than the dark anterior notopodials. The shaft is more strongly curved distad and ends in a socket that is more asymmetrical, one of its sides rising considerably higher than the other, but still more conformable to the homogomph than to the heterogomph type of Claparede (Annelides Chetop. Golfes Naples, Suppl., 1870, p. 42). The distal end of the shaft is a little clavately enlarged. The shaft is strongly cross- striate, the striations commonly in two contiguous bands. The terminal piece is narrow, moderately short, and narrows to an acute tip. It is closely, finely setose along one edge. It varies in length, that of the most dorsal ones in the series being longest. While the neuropodial setae in the anterior parapodia much exceed the notopodials in number, behind the elytra the notopodials in- crease in number until they much exceed the neuropodials in the posterior part of the anterior series and in some succeeding oens of the second series. Begin- ning with the twelfth parapodia, this second type of setae is abruptly replaced both on notopodia and on neuropodia by a thii-d type differing especially in being larger and in having the terminal piece much larger and broader, more paddle-like, widening from the base to distad of the middle, and then again narrowing to the acute or subacute tip. The terminal piece along one edge is very finely and shortly serrate. (Plate 29, fig. 6). Some of the notopodials, e.g., those of the twelfth parapodia, have much shorter terminal pieces, which, however, are the same in structure as the others; they are in the more dorsal position. The number of setae, both neuropodial and notopodial, much increases toward the middle of the body, where also inequality in the number of setae in the two rami becomes less or not at all noticeable. The pharynx is straight. The oesophagus is similarly straight. It is abruptly much narrower than the pharynx and bears at its anterior end the usual pair of simple caeca. (Plate 29, fig. 8). The proboscis in no case is extended. The jaws are colorless, relatively long and slender, each ^vith eight teeth. Other armatm'e was not detected in the specimen dissected. Locality. Gilbert Island: off Apaiang. Surface, by electric light. 3 January, 1900. About twelve specimens. 202 THE ANNELIDA POLYCHAETA. All of the type-specimens as preserved are flexed into a semicircle, with the concavity dorsal. The strongly narrowed anterior region, with the three pairs of large elytra, give to this form a very characteristic appearance. Aside from the peculiar tentacle, the form of the notopodial setae of the most anterior parapodia seems to be especially distinctive. Nereis Linne. Syst. nat. ed. 10, 1758, 1, p. 654; Cuvier, Rrgne anim., 1817, 2, p. 524; Audouin & Milnk Edwards, Hist.nat. Ltt. France. Annelides, 1834, 2, p. 181; Ehlers, Borstenwiirmer, 1S68, p. 450; St. Joseph, Ann. sci.nat., 1897, ser. 5, 8, p. 285; McIntosh, British annelids, 1910, 2, pt. 2, p. 267 (in part). Lycoris Savignt, Desoript. Egypte. Hist, nat., 1809 [ = 1822], 1, pt. 3, p. 29. Nereilepas Blainville, Diet. sci. nat., 1828, 57, p. 469. Heteroncreis Oersted, Annulatorum Danicorum conspectus, 1843, p. 19. Mastigonereis Schmarda, Neue wirbellose tliiere, 1861, 1, p. 107. IJohndoniu Qu.atrefages, Ann. sci. nat., 1849, ser. 3, 12, p. 304. Thoosa KiNBERG, Ofvers. K. vet. akad. Forh., 1865, no. 4, p. 172. Hedisle Malmgren, Annulata Polychacta, 1867, p. 48. Praxithea Malmgren, Op. cit., 1867, p. 50. Nereis segrex, sp. nov.i Plate 32, fig. 3-5. General color yellowish, without markings. The tentacles and cirri are whitish. The type is incomplete caudally. The portion present consists of thirty- eight somites. It is 22 mm. long and has a maximum width, exclusive of para- podia, of 3.2 miB., and inclusive of parapodia, of 4.6 mm., while to the tips of the setae, the width is 6.3 mm. The body is widest anteriorly at about the sixth somite, from where it narrows continuously caudad and also cephalad to the second somite, which is narrower than the peristomium. The body is also highest in the region of the greatest width. The prostomium in general outline as seen from above is roughly triangular. It presents a short protrusion between the palpi which is truncate and bears the tentacles. The dorsal surface in general is weakly and evenly convex except- ing for a shallow and wide median depression anteriorly. There are no traces of pigmented eyes, but colorless convex areas apparently represent them. Of these the anterior ones are much the larger. The palpi are very thick and extend forward nearly as far as the tentacles. Each is attached obliquely along ' segrex, separated from the flock or company. NEREIS SEGREX. 203 the side of the prostomium, the surface of attachment extending from base of the prostomium to within a short distance of its distal end. The basal article is weakly conically narrowed toward its end, where it is truncate. The distal article is abruptly much narrower and is subcylindric and short. The median anterior extension of the prostomium is a little constricted or grooved a short distance proximad of its cUstal margin. The tentacles, though not contiguous, are attached close together and project directly cephalad. They are subulate and wholly smooth. The peristomium above is somewhat more than two thirds the length of the prostomimB and one and a third times as long as the second somite. It is narrowest across its caudal end. The lower half of the somite, from the middle of each side across to that of the other, forms a thickened lower lip which is crossed longitudinally by numerous deep sulci. The dorsal part of the ring is smooth, or nearly so. On each side a somewhat semicircular lobe from a deeper level projects cephalad against the base of the palpus and bears the tentacular cirri. Each tentacular cirrus has a very short, relatively thick cirro- phore, the style being slender and subulate and wholly smooth. All of the tentacular cirri are short. Each anterior ventral cutus is attached at the anterior margin of the cirriferous lobe, and when laid back reaches only upon the peristomium itself or barely to the anterior border of the second sonaite. It projects normally ectoventrocephalad. The anterior dorsal cutus is attached immediately dorsad of the ventral, theu" cirrophores being contiguous at base, and projects a little ectad of dorsad. When laid back along the body, it reaches to the third somite. The posterior dorsal, which is attached just dorsad of the ventral, has a cirrophore longer than that of the others and reaches back upon the fourth somite. The metastomial somites are all essentially undivided, though in the middle region of the body they may show a shallow and rather wide transverse furrow that cxirves caudad at the ends in crescentic manner and separates off a caudal, more elevated, region. On each side above the base of the parapodium, the somite is elevated in a glandular area not present on the most anterior somites and in the more caudal ones becoming more elongate and narrow. The somites are strongly arched above and are flattened ventrally, where they show a distinct and rather deep neural furrow excepting on the first few. The somites increase in length caudad to the sixth, when they decrease and quickly attain a length that is uniform over the remaining part of the type. A typical parapodium is strongly flattened in the direction of the long axis 204 THE ANNELIDA POLYCHAETA. of the body, is deep dorsoventrally and of moderate length. It presents four subcorneal lobes, of which the two submedian ones project distinctly farther distad than the others. The dorsal lobe presents a swollen basal region of con- siderable size, from the dorsal edge of which the slender notocirrus arises and from the anterior side of which the large, basally much inflated, distally conical, process extends forwards. The notocirrus, which is slenderly tapered distad, extends to or, more commonly, clearly beyond the distal end of the main conical dorsal lobe. The ventral lobe arises near the base of the parapodium, extend- ing first ventrad and then bending distad at right angles to its basal portion. It is subconical, but is more or less abruptly reduced in diameter near the middle of its length. The neurocirrus is attached at the extreme base of the parapodium, extending ventrad in the narrow space between the ventral lobe and then curv- ing distad. It is slightly more slender than the notochrus. The notopodium is a short lobe having an oblique distal surface, with the lower angle protruding distad into a conspicuous conical process, at the dorsal edge of the base of which the aciculum emerges. This lobe extends as a low ridge or presetal membrane, a slighter one being present as a postsetal lobe. The neuropodium is a little less thick than the notopodium. At the distal end it is similarly produced into a conical lobe caudoventrad of the setae. The aciculum extends into the upper part of the process, emerging from its dorsal sm-face. The expansion of the dorsal lobe from which the style of the notocirrus arises becomes reduced in the most anterior parapodia, in the first pair appearing as an ordinary cirrophore. (Plate 32, fig. 5). There are two acicula in each parapodium, one in each ramus. They are dense black in color, and taper to a slenderly acute tip. The neuropodial acic- ulum curves conspicuously ventrad, entering the distal neuropodial process and running beneath its dorsal surface to the point of emergence. The noto- podial aciculum curves dorsad, emerging at the base of the distal process. The setae of the nevuopodial fascicles are much more numerous than those of the notopodial and are ob\'iously longer. The setae are all compound and are of two types. The notopodials are all of one type. These have slender shafts which are strongly finely cross-striate, or camerated, and end in slightly widened, symmetrical, or homogomphus, sockets. The apical piece, or blade, is long, tapering to a fine tip, and is fringed densely along one margin proximad of the smooth tip. In the neiu-opodium the more numerous setae are of the same type as those of the notopodium ; but in the ventral part of the fascicle are a number of setae of a second type. These have stouter but similarly strongly camerated NEREIS LEUCA. 205 shafts ending in unsymmetrical, or heterogomphous, sockets. The blade in these heterogomphs is short. It ends in a slender, short, distally narrowly rounded end region which is not dentate, proximad of which along one margin it is densely fringed. (Plate 32, fig. 4, 5). The proboscis is but little extruded, making a detailed account of the number and arrangement of the paragnatha impracticable. Of the areas of the oral ring, V and VI are wholly unarmed ; VII bears small, nodular paragnatha irregularly transversely arranged across its extreme distal end; each area VIII lacks paragnatha excepting a few in the portion contiguous with VII, from the group on which they are not separated and might be regarded as belonging with them rather than on VIII. All maxillary areas seem to bear a few paragnatha. These are longer and more conical than those of the proximal ring. They are few in number and isolated from each other. Locality. Off Isthmus of Panama, 72 m. S. W. of Mariato Point: Sta. 4631 (lat. 6° 26' N., long. 84° 49' W.). Depth 774 fms. Bottom of green sand. Bottom temp. 38° F. 3 November, 1904. One specimen. Aside from the distinctive nature of the arrangement of the paragnatha, a characteristic feature of this species is the uniformity in character of the para- podia, with the much enlarged proximal or cirrophorous region of the notocirrus and the much inflated dorsal lobe in front of it. In side view these enlargements in their relation to the cutus appear much like those of some species of the Alitta (Thoosa) group of Klnberg, excepting that they are not foliaceous. The non-pigmented condition of the ocular areas may be a normal and degenerate state in the species. Nereis leuca, sp. nov.' Plate 32, fig. 6-8; Plate 33, fig. 1-6. Epitokous Male (Heteronereis). Body colorless and transparent throughout, excepting the eyes, which are black as usual, though the posterior division of the body appears somewhat darkened from its contents. Total length 16 mm. Greatest width, exclusive of parapodia, 1.5 mm. The nereid and heteronereid divisions are sharply distinguished as usual, the heteronereid division the longer. The nereid division consists of seventeen ' XeuKos, colorless. 206 THE ANNELIDA POLYCHAETA. somites of which sixteen are setigerous, the heteronereid of about sixty, giving a total of nearly seventy-seven. The anterior division is of uniform width from its caudal end to the middle, from where it narrows a Uttle forward to the pros- tomium. The posterior di\'ision is widest near its anterior end from where it narrows uniformly to the caudal end. The prostomium is quadrangular with a much narrower median process extending forward in front of the eyes. It is wider than the total length in about the ratio eight to seven. The preocular process has above a shallow, median longitudinal furrow. The four eyes are equal and moderate in size. Those of the two pairs are the same distance apart and the two of each side are contiguous. The lens of each anterior eye is directed dorsocephaloectad, that of each posterior one dorsocaudoectad. The tentacles are attached on the lower border of the preocular lobe and project cephaloventrad. They are slenderly subulate. The palpus is attached caudoectad of the corresponding tentacle, below the angle at the junction of ocular and preocular divisions of prostomium, and projects a little cephaloectad of ventrad. The proximal article is long and thick, a little compressed, so as to present an elliptic cross-section; the apical article is small and distally rounded. (Plate 33, fig. 1). The peristomium is, as a whole, shorter than the succeeding somite. It is divided by a distinct transverse fmTow as in caenocirrus ; the anterior division is the shorter, is again divided by a secondary furrow and is mesally usually convex, but does not project over the prostomium as it does in caenocirrus. The tentaciilar cu-ri are all comparatively short, slender, gradually tapered, and closely jointed or varicose. Of the four pairs the posterior dorsals are long- est, but reach only to the fifth or beginning of the sixth somite. The posterior ventrals and anterior dorsals are equal in length, reaching to the third somite. The anterior ventrals are shortest, reaching only to the second somite. The tentacular cirri are attached in the usual places. (Plate 33, fig. 1). The metastomial somites of the nereid division of the body are dorsally high and convex; ventrally the arch is lower and mesally flattened and with a rather deep neural furrow. They are smooth and entire. These somites increase in length to near the fifth, after which the length remains uniform or nearly so. In those of the middle and posterior parts of the division the width is three and three fourths to four tunes the length. In the heteronereid division the somites are more compressed dorsoventrally and are shorter and more closely arranged. The pygidium is very small, somewhat trapeziform in outline, with the caudal margin notched. No cirri are present in the type. NEREIS LEUCA. 207 The parapodia of the nereid di\dsion are of the common general form, short, deep dorsoventrally, and in anterocaudal diameter narrowing distad. The parapodia increase gradually in length caudad ; but the relative sizes of the two rami remain essentially the same. The rami short, the notopodial with two short ligulae, the neuropodial with one. In the character of the notocirri the anterior parapodia fall into two groups, as usual. Those of the first group, consisting of but the first five pairs instead of the more usual seven, bear spe- cially modified notocirri, each of these presenting a thick, subcylindrical body narrowing at base and again abruptly distad to pass into a slender apical style or tip. The remaining anterior parapodia have notocirri of the usual type, the styles much more slender and tapering gradually from base to tip. In all cases the notocirri are attached close to the distal end of the notopodium, both in the anterior and in the posterior group. As to the neurocirri, there are not two such sharply defined groups as are frequently present. The first two pairs are slightly more swollen at base than the others, but the transition is not so abrupt as usual. The neiu'och-ri are all attached at base of nem-opodia which they exceed in the anterior pairs. They become relatively shorter in going cau- dad. The parapodia of the heteronereid di\ision are characterized, as usual, by their greater length, which increases to the middle region of the division, again gradually shortening caudad, by their greater relative thinness in the caudo- cephalic direction, and especially by the laminate developments and the long natatory setae. The notopodium is larger than the neuropodium and the sinus between the two is rather deep. All the laminae are relatively smaller than usual. The two Ugulae of the notopodium have the usual relative size, form, and position, the dorsal one being narrowly lanceolate, the ventral one, attached by its edge on the ventral side of the ramus, is larger, distally acuminate, and presents a distinct auricle proximaUy. Both laminae are much shorter than the shafts of the setae, extending but little distad of the middle of the latter. The principal lamina of the neurocuTus is narrowly subovate, distally narrowly rounded, with the usual small auricle on each side proximally, the two auricles asynunetricaUy placed with reference to each other. The dorsal neuropodial Ugula is small and more of the form of an ordinary style, being constricted at base and narrowed to a point distad. It curves distad close to the edge of the large lamina. The notocirrus is slender, tapered to a fine tip. It exceeds the laminae, reaching to or beyond the ends of the shafts of the setae. On the dorsal side of its base it bears a small, semicircular lamina attached at one side. It is rather vaguely pseudojointed, but bears no distinct papillae along 208 THE ANNELIDA POLYCHAETA. one side. The neurocirrus is smaller than the notocirrus and similarly slender. It bears the usual lamina on each side of its base. (Plate 33, fig. 2-4). The acicula are two and have the ordinary form and coloration, black or nearly so, excepting for a colorless proximal portion. Only the notopodial acic- ulum is normally developed in the anterior four pairs of parapodia. Acicula of the nereid division in general are notably smaller and less conspicuous than those of the natatory parapodia. The setae of the anterior parapodia are of thi-ee types. First, homogomphs, with long, slender, tapering end pieces with fine smooth tips above the marginally setose portion. Second, heterogomphs, much less numerous, which have similar end pieces, but these shorter, and especi- ally so the tips. And third, heterogomphs with shorter end pieces having a short, narrowly rounded tip above the broader portion that is setose along one edge. The shafts are striate as usual. The notopodial setae of the anterior parapodia, of which none at all seem to be present in the first several pairs, are when present, fewer in number than the neuropodials and are shorter and finer. They are homogomphs, otherwise like those of the neuropodium, but with shorter terminal blades. The natatory setae of both neuropodia and notopodia are numerous and of the ordinary type. They are homogomphs with double, striated bands in the shafts, wdth oar-like terminal blades widening distad and ending in a mucronate apex, and with very fine teeth of uniform character along one side. (Plate 32, fig. 6-8; Plate 33, fig. 5-6). The proboscis is but slightly protruded. The paragnatha are separate, small, corneus cones of the Nereis type. The maxillae are large, with teeth coarse and distally blunt. Locality. Marshall Islands: off Rongelab Island. Surface by night light. 17 January, 1900. One male. This species may be characterized by the form of the prostomium and the position and size of its eyes and palpi ; the transversely divided peristomium in which the anterior division is not angularly extended forward; the short tentacular cirri, of which the longest reach only to the fifth somite; the number of somites in the nereid division, sevente.en, with specially modified cirri on only the fii'st five pairs, and with no neurocirri strongly modified, only the first two pairs being at all noticeably different; and the small size of the laminae of the natatory setae. NEREIS CAENOCIRRUS. 209 Nereis caenocirrus, sp. nov.^ Plate 33, fig. 7, 8; Plate 34, fig. 1-6; Plate 35, fig. 1, 2. The body in general is colorless, or weakly brownish, probably from preser- vation, the nereid division in particular being translucent. Eyes black. Ten- tacles and cirri colorless and translucent. Setae also colorless and transparent. The larger type-specimen is 16 mm. long with the maximum width, exclusive of parapodia, 1.6 mm., and inclusive of parapodia and setae, 3.4 mm. The body is constricted at the junction of its two principal divisions. The nereid division narrows strongly cephalad and less markedly at. its caudal end. The hetero- nereid division is widest a little in front of its middle from where it narrows slightly forward and gradually and strongly caudad. The number of somites in the nereid division is fifteen and in the heteronereid division fifty-five and sixty, making the total number in the two types seventy and seventy-five respec- tively. The prostomium consists of a principal, posterior, ocular division, quadi-angu- lar in outUne as seen from above, and a low, sub triangular, apically rounded pre- ocular division. Its length is about tlu-ee fom'ths the width and is greater than the combined length of the first three somites, but less than that of the first four. The four eyes are of but moderate size and are very nearly equal, the anterior ones being sUghtly larger. The eyes of each of the two pairs are sepa- rated by an equal distance. The eyes on each side are contiguous, \vith the ante- rior one cephaloventrad from the posterior. The lens of each posterior eye is directed a little ectad of dorsad. Each anterior eye is more lateral in position, with the length directed cephaloectad. The tentacles are attached beneath the anterior end of the prostomium and project directly ventrad. They are slender, tapered and short, about equalling the length of the proximal article of the palps. The palps are attached on the ventral surface between the anterior eyes, wliich they exceed in diameter. They are separated mesally and project directly ventrad. The proximal article in each is stout, cyUndi'ical and long, while the distal article is abruptly much narrower, and short and rounded. (Plate 34, fig. 1). The peristomium above presents an anterior border of wide, but very low, triangular form. The apical angle very obtuse. The somite is divided by a deep transverse sulcus which is weak laterally but is again strong ventrally. ' Koicot strange, and cirrus. 210 THE ANNELIDA POLYCHAETA. As a whole it is clearly longer above than the succeeding somites. On each side it widens strongly, projecting forward beneath the eyes, as usual, and ven- trally it is longer than the two succeeding somites combined, though shorter than the three. The tentacular cirri are all short, strongly tapered to a point distad, and varicQse, or imperfectly jointed, more distinctly so in the distal part. The anterior ventral cirri are shortest. Each is attached in the exterior angle between palp and elevated buccal border and reaches only to the second somite. The anterior dorsal on each side is attached just above the ventral one and at the posterior border of the anterior eye; it extends to the edge of the fifth somite. The posterior ventral tentacular cirrus on each side is attached sUghtly caudad of and on a level with the anterior dorsal, than which it is a Uttle shorter, reaching to the fourth somite. The posterior dorsal tentacular cirrus on each side is attached between the ventral one and the lower margin of the posterior eye. It is the longest of the four, reaching to the seventh somite. The border of the mouth is elevated excepting on the anterior side and is crossed radially by sulci at moderate distances. (Plate 34, fig. 1). The metastomial somites of the anterior division are moderately convex above and below. They are simple and entire, though a few of the more anterior ones may show dorsally a weak transverse sulcus over the middle portion. The first of these somites is shortest, the others increasing in length to the fifth, after which they are nearly of uniform length. In the widest part of the division, e.g., near the seventh metastomial ring, the width of each somite is about three and one half times its length. The somites are all distinctly separated. In the pos- terior division the somites are more depressed. The intersegmental furrows are deeper above than below. The pygidium is short and broad, broadest at middle of length, distad of which it is convex. The anal cirri are moderate in length, slender, and tapered, and varicose. The parapodia of the anterior or nereid division of the body are biramous and of the usual general character. They increase in length from the first to those in the widest region of the body, those of the last few somites of the divi- sion again decreasing. In the most anterior parapodia the neuropodium pre- sents at the distal end a short and conical, distally rounded lobe, or ligula, ventrad of the setae and a short, blunt acicular lobe. Caudad this lobe becomes stouter and blunter. The first five parapodia lack notopodial acicula. Caudad the notopodium relatively to the neuropodium becomes longer and longer, project- ing much beyond the latter. On its dorsal side is a stout, subconical lobe which does not extend as far distad as the acicular lobe. In the character of the noto- NEREIS CAENOCIRRUS. 211 cirri the parapodia form two sharply defined gi'oups. In the fii-st, embracing the first seven pau's, the style of the notocirri from a constricted base expands into a conspicuously large body, from the distal end of which extends a very slender tapered process, Uke a slender beak from a bird's head. In the second group, embracing the eighth to fifteenth pairs, the notocirri are of the ordinary form; slenderly uniformly tapered from the base distad. The notocirri of the most anterior parapodia of the nereid division are attached near the distal end; caudad the point of attachment shifts farther proximad and in the last ones is near the middle of the notopodium. As to the character of the neurocirri there are also two groups. The first of these embraces the first five pairs in which the form is very similar to that of the anterior notocirri, presenting a large expanded middle bodj^ from the distal end of which a very slender, short, oblique distal process extends. On the succeeding parapodia they have the usual slender, distally attenuated form, and decrease somewhat toward the caudal region. The first of this group are broader proximally and somewhat flattened. All neurocirri attached near the base. The natatory parapodia of the heteronereid division present the usual general differences from the others, being as a whole longer, deeper, and much flattened in the anterocaudal direction, and bearing large and conspicuous fohaceous developments. The notopodium bears two of these thin, finely veined, transparent appendages. One on the dorsal side, attached near thenotocirrus, is slenderly lanceolate and does not attain the ends of the shafts ot the setae. The other is attached on the ventral side, is much larger, and presents the usual auricle proximally on the ventral side of the neu- ropodium, well proximad of the distal end. It is symmetrically pointed distad and is abruptly narrower just below its middle. From the distal end of the neuropodium arises a very large, subcordate appendage, distally well rounded, with a rather narrow, curved, auricular appendage on the dorsal side at base. The notocirrus bears on the dorsal side of its base a subeUiptic fohaceous body attached by one side ; the style itself is about equal in length to the cirri ; below a slender, transparent, smooth tip there is along the side toward the setae a series of unusually long, well separated and conspicuous enlargements. The nem-o- cuTus presents a short, thick cirrophore, from which rises a style of the ordinary sort and two membranous appendages, a narrowly oblong, weakly sigmoid one on the distal side of the style and, on the proximal side, a much larger one of subdeltoid outhne. In the caudal region the same parts are present, but become much smaller. Apparently in the last three pans the fohaceous appendages are aU lacking, the styles of the cirri being long and conspicuous, with the other 212 THE ANNELIDA POLYCHAETA. parts relatively much reduced. (Plate 33, fig. 8; Plate 34, fig. 2, 3; Plate 35, fig. 1, 2). Two acicula occiir in each parapodium excepting those of the first five pairs, in which only the neiu-opodial is normally developed. The typical acicula of the heteronereid region are sUghtly curved and distally acute, with the proxi- mal half colorless or nearly so and the distal half abruptly black or reddish black. In parapodia of the anterior region the acicula in general are similar. In addi- tion to the aciculum there is normally present in the notopodium of this region a single stout seta, simple, but with a suture evident in obsolete condition, thicker than the aciculum, which often protrudes freely from the surface and is strongly hooked at the tip, with the distal portion dark in color, the proximal pale; the cross-striated band is single. No notopodial setae other than the uncinate ones are found in either of the types on any of the parapodia of the nereid division, their absence being apparently normal. The neuropodials of all these parapodia are weU developed. They are compound heterogomphs of two types. The first type, few in number and occm'ring on the dorsal side of the fascicle, have the distal piece slenderly tapered and smooth, tip long and fine. The striated band of the shafts is single except distally. In the second and more abundant type the distal piece is much shorter, with the smooth tip short and distally rounded and the setae extending up close to it. The natatory setae are much larger and coarser than the anterior forms. The shaft is strongly cross-striate in the usual double band and terminates in a homogomph socket. The distal piece is paddle- like, clavately widening distad, at the distal end convexly rounded to a minute mucron at the tip; very finely toothed along one side. All are similar in both notopodial and neuropodial fascicles. (Plate 33, fig. 7; Plate 34, fig. 4-6). Proboscis not extruded in either type, though the maxiUae extend a Uttle from the mouth. The paragnatha are all conical, acute, and dark in color. They occur in all the areas, but are much more abundant in those of the maxillary half. Locality. Marshall Islands: off Rongelab Island. Sm-face by night light. 17 January, 1900. Two males. This species is strongly characterized by the highly modified notopodial setae of the nereid division, of which but one is present in each notopodium. In these the distal piece is fused with the proximal and is uncinate, the seta as a whole being stouter than the aciculum, dark in color, and conspicuous. An- other marked characteristic is in the form of the notocirri of the heteronereid division, these having along one side a series of papillae of unusual length, above which a more slender, smooth tip ordinarily projects at an angle to the main axis. CERATONEREIS FAKARAVAE. 213 Nereis pelagica Linne. Syst. nat., cd. 10, 1758, 1, p. 654; Blai.wille, Diet. sci. nat., 1828, 57, p. 470; Quatrefages, Hist. nat. annelcs, 1865, 1, p. 542; Ehlers, Borsten^viirmer, 1868, p. 511, pi. 20, fig. 11-20; McIntosh, British annelids, 1910, 2, pt. 2, p. 267, pi. 52, fig. 1, 2, pi. 60, fig. 6, 6a, pi. 71, fig. 7, 7i, pi. 80, fig. 25, 25b. Nereis fernujinea Gunxer, Skrift. Kjobenb. selskab., 1770, 10, p. 169, pi. e, fig. 10. Nereis verrticosa O. F. Muli.er, Zool. Daiiica prodr., 1776, p. 217. Nereis fimbriata O. F. Mui.ler, Op. cit., 1776, p. 217. Nereis margalicera Blaixville, Op. cit., 1828, 57, p. 470; Qu.atrefages, Op. cit., 1865, 1, p. 510. Lycoris inargaritacea Johxstox, Zool. journ., 1829, 4, p. 420. Lycoris viridis John.ston, Op. cit., 1829, 4, p. 419. Nereis fulgens Daltell, Pow. creat., 1853, 2, p. 153, pi. 22, fig. 6-8. Heteronereis arclica Oer.sted, Nat. tids., 1842, 4, p. 117 (epitokous female). Heteronereis assi?n.His Oersted, Op. cit., 1842, 4, p. 117 (epitokous female). Nereis renalis Johxston, Ann. nat. hist., 1840, 5, p. 176 (epitokous male). Heteronereis arctica Oersted, Gronlands Annulata dorsibranchiata, 1843, p. 179, fig. 50, 51, 60, 65, 68, 70 (epitokous male). INereilepas fusca Oersted, Annulatorum Danicorum conspectus, 1843, p. 21, fig. 49, 50 (epitokous female). Nereis grandifolia H. Rathke, Beitr. fauna Norweg., 1843, p. 155, pi. 7, fig. 13, 14 (epitokous male). Nereis denlicidata Stimpson, Invertb. Grand Manan, 1853, p. 33, fig. 23 (epitokous female). Nereis reynaudi Qu.\tref.\ges, Op. cit., 1865, 1, p. 519. Nereis bowerbanckii Quatref.\ges, Op. cit., 1865, 1, p. 541. Locality. Two specimens in the collection bear simply the label "Alba- tross, 1886." They doubtless come from the Atlantic North American Coast, and probably off southern New England. The species is common off both shores of the Atlantic and occurs also in the Pacific. It is found between tide-marks and at moderate depths. Ceratonereis Kinberg. Ofvers. K. vet. akad. Forh., 1865, no. 4, p. 170; St. Joseph, Ann. sci. nat., 1897, ser. 5, 8, p. 285. Nereis (Ceratonereis) Gravibk, Nouv. arch. Mus. hist, nat., 1900, ser. 4, 2, p. 157, 172. Ceratonereis fakaravae, sp. nov. Plate 35, fig. 6-8. The type-specimen bears eighty-eight pau's of fully developed parapodia in addition to three smaller pahs on a regenerating caudal tip. Length 65 imn.; greatest width between bases of the parapodia (third and fourth somites), 4 mm. ; between tips of parapodia at same point, about 5.25 mm. Prostomium clearly wider than long, in a ratio of about five to four. Pre- ocular portion rectangular, abruptly and considerably narrower than the ocular, which is narrowed forwards and has its anterior margin semicircular, marked 214 THE ANNELIDA POLYCHAETA. above with a median longitudinal furrow, which is rather deep. Posterior eyes at extreme caudal edge of prostomium, the same distance apart as the anterior ones, or very nearly so, transversely subelUptic. Tentacles narrowly conical, separated at base by nearly then- basal diameter, nearly equal in length to the first joint of the palpi. Palpi prominent, about four fifths as long as the prostomium, the proximal joint about three fifths as long as the prostomium; apical piece abruptly narrower, roundly subconical. Peristomiimi along median dorsal hne a little more than three fifths as long as the prostomium; laterally longer than the prostomium. Tentacular cu'ri short, the posterior dorsals reaching to the fourth metastomial somite; the anterior dorsal reaching upon the first or scarcely to the second, and both ven- trals not wholly attaining the first. The immediately succeeding segments are much shorter than the peristomium. The parapodia are short and of nearly the same length tlxroughout. Both notopodial and neuropodial fascicles of setae, excepting in the first two pairs, in which the notopodial setae are lacking. In the parapodia of the first and second pairs, and of the thii'd on one side, the notopodiima is a simple conical process which its cirrus about equals in length. The neuropodium is divided into three lobes, a major ventral one of nearly the same size as the notopodium, and two more slender, dorsal ones, the setae arising between the two dorsal lobes, of which the anterior is the more slender, and between the latter and the main or ventral lobe. In the succeeding parapodia the structure of the neuropodium is similar, but the notopodial process becomes trilobed, the more ventral lobes being more slender and aU conicocylindrical, distally well rounded. The anterior lobe is the most slender. The setae arise caudad of this anterior lobe and between it and the main lobe. In the first or most anterior parapodia, the parapodial lobes are very nearly equal in length. Caudad the anterior lobe of the notopodium becomes shorter and shorter, and finally practically disappears; at the same time the dorsal and more ventral notopodial lobes become manifestly longer and proportionately more slender, the cirrus upon the former elongating proportionately, and conspicuously exceed- ing the dorsal Ugula. Whereas in the first parapodia the ventral lobe of the parapodium is stouter than the other two, caudad the upper lobes gradually fuse at their bases and then farther distad form essentially a single setigerous lobe much thicker than the ventral one, on which the cirrus becomes short, slender, and inconspicuous. Acicula stout and black. Setae all compound. The setae of the anterior parapodia are all alike, long and very slender, with the shafts of the usual struc- UNCINEREIS. 215 ture. In the other parapodia the setae of the notopodia continue to be all ahke and of the slender type; but in the neuropodium some much stouter setae occur, these having a diameter three times or more that of the more slender ones. Blades of the stouter setae short, socket lateral and obhque, below distal end of shafts. The blades of the ordinary setae moderately long and acuminate, the tips capillary and moderately curved; the blade mth a series of short hairs or teeth along the concave side, excepting distally. Socket symmetrically formed in the regularly expanded distal end of the stem. (Plate 35, fig. 6, 7). Paragnatha absent from basal region. In I are two paragnatha, one in front of the other. In IV a row of three stout pai'agnatha, those of III few, those of II uncertain. jVIaxillae black, cutting edge proximally entire, distally wavy, forming two or three inconspicuous crenulations. Body anteriorly reddish, becoming m the middle and the caudal region yellowish. Parapodia yellow, the contents of a large basal region of notopodia showing as a black dot in the middle and caudal region. A whitish area on base of prostomium. Locality. Paumotu Archipelago: Fakarava. Fringing Reef. 12 October, 1899. One specimen. Characterized especially by its short prostomium, long peristomium, un- usually short tentacular cirri, and the two paragnatha in area I. Uncinereis, gen. nov.^ Prostomimn with broader posterior region and a preocular region narrow- ing anteriorly. Two pairs of eyes. Tentacles two, attached anteriorly and projecting forwards. Palps large and two jointed, the distal article compara- tively large. Peristomium bowed forward above and ventrally extended caudad into a broad excavation in the second somite. Bearing four pairs of tentacular cirri in which ceratophores are weU. developed. Parapodia biramous, each branch bilobed, and the notopodial setae emerg- ing in the interval between the two upper lobes. The lobes of from four to seven pairs of parapodia following the first foiu- pairs, subspherically swollen, all others conicaUy pointed. Setae of three types, composite setae of homogomph and heterogomph forms, and in addition stout crochets present in most notopodia. ' uncinus, hook, hooked seta, and Nereis. 216 THE ANNELIDA POLYCHAETA. Proboscis armed \vith numerous corneous paragnatha arranged in close series (pectinate) as in Platynereis. Genotype. — U. suhita, sp. nov. In addition to the type-species, Nereis agassizi Ehlers, and apparently also N. notomacula Treadwell and N. kobiensis Mcintosh fall into this genus, of which the most saUent distinctive character is the presence of the hooked setae or crochets in the notopodial fascicles. These are much hke those present in Ivunbrinereids, but are not known to me to occur in other species of Nereis, Platynereis, or related genera. The species of Uncinereis agree closely also in various other characters. All at present known are from the Pacific. Uncinereis stjbita, sp. nov.^ Plate 30, fig. 1-4. The general color of the preserved specimens is a dense brown. The ten- tacles and cirri are much Ughter, yello\\'ish. The type is incomplete caudally. It consists at present of sixty somites and has a length of 22 mm., with a maximum width, exclusive of the parapodia, of 1.8 mm. The body is widest and highest in the region of the fifth somite, from where it narrows and lowers cephalad and, more gradually, caudad in the usual way. The prostomium is nearly equal in length and breadth. It is widest near the middle at the level of the anterior eyes from where it narrows a Uttle caudad and more strongly cephalad, with the anterior end widely subtruncate, being a little more extended forward at middle than at end, and in outline appearing much hke that of U. kobiensis (Mcintosh). The preocular region is flattened above and depressed below the level of the broader posterior region. The eyes are nearly equal in size. The posterior ones are only shghtly nearer together than the anterior and have their axes directed more dorsad. The posterior and anterior eyes on each side are nearly contiguous. The tentacles are not contiguous proximally. They are moderately long, a little exceeding the length of the prostomium, and are slender and gradually acuminate distad as usual. The palpi are nearly as long as the tentacles. The proximal article is about as thick as the width of the prostomium across its anterior end. The distal ' subire, to go under, descend. UNCINEREIS SUBITA. 217 article is very nearly as long as the proximal one and is about two tliirds as thick ; it is cyhndrical, with the distal end strongly rounded. The peristomium above is bowed strongly forward over the base of the prostomium. It is clearly shorter above than the prostomium and is, in the median dorsal line, very sUghtly or not at all longer than the second somite, than which at the sides it is ob\dously shorter, though ventrally decidedly longer. On the ventral side it curves back as a broad projection into the second somite, the sides of the produced area being concave, and the caudal margin wide and straight. This caudal region is set off by a weak transverse furrow. The ventral area of the prostomium is crossed by numerous fine longitucUnal sulci which are toward each side moderately oblique. The anterior margin is straight, curving back slightly on the sides. The tentacular cirri are inserted as usual. The ventral ones are much more slender and shorter than the dorsal, the anterior ones reaclaing to the thhd somite and posterior to the fourth. The ceratophores are short, cyhndrical, and a Uttle thicker than the styles at base. The dorsal cirri have ceratophores that greatly exceed those of the ventrals, that of the posterior dorsal also clearly exceeding that of the anterior. The anterior dorsal reaches to the sixth or seventh somite, the posterior dorsal to the twelfth or thirteenth. The metastomial somites decrease in length to the fifth after which they remain of nearly uniform length. Each of the most anterior ones is bowed conspicuously forwards at the sides. They are highly arched above, though across the top somewhat depressed and with a weak median longitudinal sulcus. They are strongly flattened ventrally, extending but slightly below the level of the parapodia, and have a well-marked neural furrow. A parapodium from the middle region of the body is short and deep, the dorsoventral diameter or depth exceeding the length. It is flattened in the direction of the axis of the body, as usual. The undivided basal division is much longer dorsaUy than ventrally, its distal side being obhque and straight. It bears the usual four lobes. The notopodium shows a subcyUndrical lobe, narrow- ing toward the base and subconically distad, which lies below the setae, this rising from a very low conical process of the basal division of the parapodium much shorter than the infrasetal lobe. The infrasetal lobe is longer than the crochets, but shorter than the other setae. The neuropodium projects as a distinct subcorneal lobe as long as but thicker proximally than the infrasetal notopodial process. At the distal end it presents a short, rounded, presetal and a postsetal lip, which are equal in length, or nearly so. The dorsal lobe pre- 218 THE ANNELIDA POLYCHAETA. sents a thick, obliquely placed base shaped like the frustrum of a cone, from the distal surface of which projects a slender, cylindroconical process proper, which exceeds the other lobe in length, and contiguously with it the notocirrus, which is subfiliform, but tapers gradually distad, and is very long, much exceed- ing the parapodial lobes in length and, when laid back caudad, extending entirely across the succeeding two somites. The ventral lobe arises at the base of the neuropodial lobe proper, which it sUghtly exceeds in length and than which it is more slender, being of nearly the same form and size as the infrasetal notopodial lobes. Just proximad of the ventral lobe arises the neurocirrus. This has a small, low, subcorneal cirrophore and a slender style which reaches to near the tip of the ventral lobe. The neurocirrus remains of uniform proportions through- out, but the notocirrus decreases both in relative and in actual length both to- ward the anterior and toward the posterior end of the body. The notopodial lobe is stouter in the widest region of the body, that is, on the somites imme- diately following the fifth, and the ventral and dorsal lobes of the same region are also much stouter. (Plate 30, fig. 1). In a typical parapodium of the middle region of the body there are setae of three distinct and well-marked types. In the notopodial fascicle are usu- ally two stout crochets, each of which distaUy curves first strongly dorsad and then bends ventrad and proximad into a thus somewhat recurving, acute tooth or beak, on the distal curve of which is placed a small, colorless, and transparent rounded tooth or nodule, the main process and distal end of the curved portion of the crochet being dark browai and the remainder of the shaft colorless. A thin transparent process, or keel, extends from the shaft to the tip of the principal tooth. In the notopodium there are in addition compound setae. In these the shafts are finely cross-striate, or camerated, and end in symmetrical sockets. The blades are long and finely tipped, and are finely pectinate below the smooth tip on one side. In the netu-opodium, in addition to homogomphs of this type, there are compound setae with unsymmetrical sockets and blades that are short, with small, narrow, and distally rounded tips below which they are finely pectinate on one side in the usual way. The maxillae have short, acute, only shghtly incurved, smooth fangs, below which are six short and mostly blunt teeth. The paragnatha are all corneous and are pectinate, being arranged densely in munerous, transverse rows. Their precise distribution was not satisfactorily determined from the partial dissec- tion, the proboscis being wholly retracted. Locality. Off E. point Santa Rosa Island, California; Sta. 4571 PLATYNEREIS POLYSCALMA. 219 (lat. 33° 40' N., long. 119° 35' W.). Depth 900 fms. 7 October, 1904. One specimen. A characteristic feature of this species is in the structure of the stout crochets in the notopodial fascicles, which in details is obviously different from that of the crochets of U. agassizi. The latter is a larger and proportionately stouter species with a broader head, shorter tentacles, palps having the distal article relatively clearly shorter, and with the notocirri in the middle region much shorter. It is common on the coast of California in the littoral zone down to 60 fms. Platynereis Kinberg. Ofvers. K. vet. akad. Forh., 1865, no. 4, p. 177; St. Joseph, Ann. sci. nat., 1897, ser. 5, 8, p. 286; Gravier, Nouv. arch. Mus. hist, nat., 1901, ser. 4, 3, ]). 155, 197. Iphivercis M-\i.mgren, Nordiska hafs. annulater, 1865, p. 181. Leontis Malmgben, Annulata Polychaeta, 1867, p. 52. Platynereis polyscalma, sp. nov.^ Plate 30, fig. 5-8; Plate 31, fig. 1-10; Plate 32, fig. 1, 2. Epitokous Male (Heteronereis). The general color is dull yellow, with the eyes soUd black and the preocular portion of the prostomium colorless and translucent. The cirri also colorless. Under the lens it is seen that in the posterior division there is dorsally a minute spot or short streak of purplish color on the base of each parapodium and also a longitudinal middorsal series of spots of the same color becoming fainter cephalad and not extending into the anterior region, whereas the lateral series may do so; on the ventral surface of the posterior division similar series of purpUsh dots occur with usually additional markings farther distad on the para- podia and ventral cirri. Setae colorless and transparent. The largest specimen in the collection is 20 mm. long with a maximum width, exclusive of the parapodia, of 2.1 mm. The body is widest near the middle of its length and narrows to a slenderly acute caudal tip and also decidedly cepha- lad, the body also appearing more or less constricted at the junction of the nereid and heteronereid divisions. The number of somites in the anterior or nereid division of the body is apparently always fifteen. In the heteronereid ' 7roX(rjKoX;uos, many oared. 220 THE ANNELIDA POLYCHAETA. division the number may be as high as ninety-five, giving a maximum total number of somites of about one hundred and ten. The prostomium as a whole is very elongate and is much longer than wide (about in the ratio of seven to four). It presents two sharply defined divisions, a somewhat broader, more opaque, posterior division bearing the eyes, and in front of this a translucent area which is rounded anteriorly, is flattened dorso- ventrally, and on its ventral surface bears the tentacles. The preocular division is scarcely more than two thirds as long as the posterior. Of the four eyes the anterior pair are greatly larger than the posterior; they are nearly wholly ventral in position, and are ventrally but narrowly separated. The lenses are directed ectoventrad. The posterior eyes are dorsal in position, each occupying an extreme ectocaudal comer of the prostomium. They are broadly elliptic in outline as seen from above and the anterior end of each extends a little over the posterior region of the cori'esponding anterior eye. The tentacles are attached on the ventral sui'face a little caudad of the ventral border. They are contiguous at base, short and conical in form, and usually extend either ventrad or, more commonly, directly caudad, lying against the prostomium and reaching about half the distance from the point of attachment to the basal division of the prostomium. The palpi are very peculiar. In each the proximal joint is fixed along one side to the ventral surface of the prostomium, its distal end lying a little caudad of the posterior edge of the anterior eyes, from where the joint reaches forward between the eyes, narrowing conspicuously forward and merging with the prostomium before reaching the level of the anterior edge of the eyes. The distal joint extends directly caudad over the border of the mouth. It is conspicuously wider than the proximal joint, is well rounded, and but slightly longer than broad. (Plate 31, fig. 2). DorsaUy the peristomivmi is produced forward over the prostomium mesally in the form of a conspicuous, usually very acutely tipped, triangular flap beneath which the prostomium is correspondingly depressed. On each side of this the dorsal eye projects back to the second somite over the peristomium. On the ventral side the peristomium is much longer, not fully as long as a ventral eye. The border of the mouth is broad and elevated and is strongly finely radially wrinkled as usual. There are the usual four pairs of tentacular cirri. The ven- tral cirri of the anterior pair are attached on the ventral surface between the anteroectal border of the mouth and the corresponding eye on each side. Each narrows to a slender acute tip and reaches caudad to the fifth somite. The dorsal cirrus of the anterior pair is attached just ectad of the base of the veiitral PLATYNEREIS POLYSCALMA. 221 one and contiguously to it. It is stouter than the ventral one and reaches to the eighth or ninth soniite. The ceratophore is short and cylindrical, is usually as thick or nearly as thick as the style at the base of the latter, and is annulate. The style is strongly varicose or irregularly jointed. The ventral cirrus of the posterior pah- is attached just caudad and a httle dorsad of the base of the anterior dorsal. The style is swollen toward the ceratophore, running out distad to a slender tip and reacliing caudad to the fifth to seventh somite. The pos- terior dorsal tentacular cirri are broken off in all the types, but judging from the basal portions, they must be somewhere near the size of the anterior dorsals. Each is attached just above the con-esponding ventral one. (Plate 31, fig. 2). The' setigerous somites are all very short. They are arched but moder- ately and about equally above and below, the body in general being somewhat lenticular in cross-section with the ventral arch a httle flattened. Dorsally the somites are entire and are crossed longitudinally by well-separated striae over the entire arch. Ventrally a longitudinal neural band is set off by furrows, laterad of each of which on each somite of the anterior division there is a trans- verse sulcus extending toward base of parapodium and thus bisecting the somite, though these sulci are not uniform. There are also some light longitudinal striae. The pygidium is very small, subtrapeziform in outUne, with the two cirri small and subcorneal. In the nereid division of the body there are two groups of parapodia sharply distinguished by the character of the notocirri, the eighth and succeeding para- podia having notocirri abruptly much smaller and different in shape from those preceding. The notocirrus of the first parapodium has a short, thick cirrophore with the style thick, swollen at base, above which it presents a long, much more slender, angularly bent part which is distaUy flattened and on one side of the end presents a short angular process. In the second parapodia the style of the notocuTus is distally much broader and the terminal extension is larger. In succeeding parapodia the notocirri increase in length and expand more and more distally, the style being flattened and enlarging clavately distad, the distal expansion presenting from its distocaudal angle an acutely pointed process projecting caudad or ventrocaudad and appearing Uke the beak of a bird from its head. In the seventh parapodia the notocirri project distinctly beyond the tips of the setae. (Plate 31, fig. 5). On the eighth parapodia the notocirrus is abruptly much shorter, with the style cyhndroconical in form and not attaining the ends of the shafts of the setae. (Plate 31, fig. 6). On succeeding parapodia to the end of the nereid division the notocirri decrease progressively in length. 222 THE ANNELIDA POLYCHAETA. All notocirri are attached toward the distal end of the parapodia. In a some- what similar way the parapodia of the anterior region are divided into two groups as to the character of their neurocirri, but these two groups do not correspond to those based on differences in notocirri. The first four pairs of parapodia are distinguished from the others in having the neurocirinis large, flattened, and abruptly narrowed to an acute and asymmetrical tip. The neurocirri of suc- ceeding parapodia of the nereid division are of ordinary form, and much more slender, conically acuminate to a finely acute tip. All neurocirri are attached well toward the base of the parapodium, as usual. The anterior parapodia are of the usual biramous and biacicular type. Aside from the low acicular process, the notopodium presents two ligulae which are short and bluntly rounded, the notocuTus being attached at the base of the dorsal one of these. The neuropodium presents a single ligula which is on the ventral side. It is short and stout and bluntly rounded, thicker but not longer than the acicular process. In the heteronereid division of the body the parapodia are longer and are strongly compressed anteroposteriorly and the appendages present the usual foliaceous developments. The notopodium has the two ligulae much enlarged, thin and foliaceous; the dorsal one is slenderly sublanceolate in out- line; the ventral one is much larger and extends proximad along the ventral edge of the notopodium into a large auricle. The neuropodium bears distally a very large, transparent, foUaceous appendage which is broadly ovate in out- line and extends proximad along both dorsal and ventral side of neuropodium into a rounded auricle, of which the ventral one is smaller and farther distad. The hgula proper of the neiu"opodium is attached on the ventral edge proximad of the end, extends first ventrad, and then distad at a right angle. The noto- cirrus presents a style of ordinary form which is strongly varicose along the ventral side and extends beyond the tip of the dorsal ligula; on the dorsal side of its base is a thin, leaf-like expansion which is rounded distally but extends proximad into an acute, auricular lobe. The neurocirrus is attached on the ventral side at the very base. Arising in the middle is the slenderly tapered style of ordinary form; on the distal side of the base arises a peculiar flattened process which projects proximad of attachment into a short process with acutely rounded tip and extends distad into a longer bifurcate appendage ; on the proxi- mal side of the style is a large foUaceous appendage extending distad into a distally rounded lobe and proximad into an acutely tipped lobe. In the para- podia of the caudal region the same parts are present, but become much reduced in size and the foUaceous appendages change more or less in shape and disappear PLATYNEREIS POLYSCALMA. 223 wholly in the most caudal region ; the shafts of the compound setae become much shorter and in the ultimate pairs only the simple notopodial ridged setae remain ; the neuropodium becomes much reduced in the penultimate pair, having only a small transparent aciculum and in the ultimate pair is scarcely at all traceable. The last pair of parapodia are especially modified, being a little longer than the penultimate paif and having the notocirri much thicker and longer, these pro- jecting and looking somewhat like special anal cii-ri, while the neuropodium is a scarcely obvious rudiment at the base on the ventral side. (Plate 31, fig. 7, 8). The acicula are two in number excepting in the most anterior parapodia, where there is but a single aciculum in each. The acicula of the anterior region are dark amber colored, those of the posterior region pale yellow or proximally colorless. Notopodial and nem'opodial acicula nearly equal in size and identi- cal in form, acutely pointed and straight or, in the posterior region, distally a little curved. The setae are mostly compound, a few in the last pair of para- podia, however, being simple. Those of the nereid division are of both homo- gomph and heterogomph types. The notopodials are homogomphs with but slightly curved shafts marked by a single, narrow, transversely striate band. The distal piece is long, slenderly acim^iinate, the naked tip being very fine and usually curved; below this on one side is the usual dense series of short setae. The neuropodials are of three types: — homogomphs hke the notopodials; heterogomphs in wliich the distal piece is much shorter with the short naked tip narrowly rounded and the series of setose teeth short, with the shaft at the distal end presenting a second cross-striate band lacking in the homogomphs; and heterogomphs in which the distal piece is hke that of the orcUnary homo- gomph above described. The natatory setae of the parapodia of the posterior division are homogomphs with shafts, as usual, strongly cross-striate and with the longitudinal striate band double. The blades are of the usual general form, being clavately widened distad, narrowed at each end. In the blade of the noto- podials there is a weak incurving on one side below the apex; in these the mar- ginal teeth toward the distal end along the incurved region are very long and spine-hke and project at right angles to the surface, while proximally these are replaced by the usual very short, fine teeth, the latter sometimes extending dis- tad so as to overlap the longer spines. In the neuropodials the blade is some- what longer, more abruptly narrowed distad, and the armed margin throughout bears only the fine short teeth. In addition, the most dorsal notopodials repre- sent a third type in which the blades are strongly transversely ridged or ribbed, the ribs in the most dorsal extending nearly to the bases of the blades, while 224 THE ANNELIDA POLYCHAETA. in the more ventral ones the ribs extend less and less toward the base. In the most caudal parapodia, as the ultimate and penult, only the ribbed setae are found; but these appear no longer compound, but rather as simple blades ribbed over most of the expanded portion. (Plate 31, fig. 9). Dissection shows the paragnatha to be very small and to be closely ranged in lines in areas III and IV. The maxillae are colorless and transparent except distally where tinged with brown. They are well curved in a direction against the flat surface. Each is relatively narrow distally, having a subacute point below which there are, in the single specimen dissected, eight rather large and obUque teeth. (Plate 31, fig. 4). Epitokous Female. The general color is duU yellow as in the male. The piuple spots on each somite are often united by fine transverse Unes of the same color. The body is moderately convexly arched above and about equally arched below. It is widest near the middle of the anterior division from where it narrows conspicuously forwards. The posterior half of the posterior division narrows strongly caudad to an acute angle. The total length of the maximum specimen is near 27 mm., with a maximum width, exclusive of parapodia, of 3 mm. In the anterior division there are typically twenty-three setigerous somites and in the posterior division from sixty to seventy, which, with the peristomium, gives a total of from eighty-four to ninety. The main part of the prostomium, occupied by the eyes, is quadrangular, the region in front of the eyes being in outline in the form of a low triangle, with the apex broadly rounded and much shorter than in the male. This apical region is more transparent, as in the male, and is similarly flattened dorsoventrally. On the ventral surface of this anterior portion are borne the two tentacles. These are conically tapered from the base, where they are contiguous, to an acute point. Wlien extended directly caudad, as seems to be usual in the pre- served specimens, they reach beyond the anterior border of the mouth and nearly to the tips of the palpi, being actually and relatively much larger than in the male. The palpi are attached on the ventral surface in front of the mouth and between the positions of the anterior eyes. The distal article of each is short and rounded, but little longer than thick. The proximal article is much thicker. The four eyes are large, though the posteriors are decidedly smaller than in the male. On each side the posterior eye is directly caudad of the ante- PLATYNEREIS POLYSCALMA. 225 rior one and nearly contiguous with it. The anterior eye is much larger than the posterior. The prostomium is dorsally mesaUy notched behind, a triangular flap from the peristomium extending into or above the notch as in the male. (Plate 31, fig. 1). The peristomium is very short as compared with the prostomium, but dor- sally is clearly longer than the second somite. It is di\aded on each side above by a transverse furrow which, toward the middle, extends forward along the side of a triangular area into the before mentioned notch of the prostomium. The tentacular cirri are strongly varicose or irregularly jointed, the joints being very short. The dorsal tentacular ciiri of the first pair are long; each is attached immediately below the interval between the two eyes; the ceratophore very short; the style gently tapered and reaching to the tenth or eleventh somite. Each anterior ventral tentacular cirrus is attached below at the lateral border of the mouth; it is subulate and reaches to the fifth somite. Each ventral tentacular ciiTus of the posterior pair is attached at nearly the same level as the dorsal of the anterior pair; it is more slenderly tapered and reaches to the eighth somite. Above it is attached the dorsal cirrus, but this in all the types is broken off near the base at which it is as thick as or a little thicker than the dorsal anterior one. The border of the mouth laterally and posteriorly is broadly elevated and is strongly radially wrinkled. The anterior setigerous somites are very short. Above, each is divided by a transverse sulcus, while one or more weaker sulci may occur caudad of this. On each side just above the parapodium each somite is crossed by a conspicuous series of longitudinal striae, these becoming weaker over the middle region of the dorsmn. Ventrally there is a similar cUviding transverse sulcus on each somite, this much more deeply impressed in the neural furrow and with faint secondary sulci on each side showing especially laterally. The pygidium as in the male; no anal cutI present in the types. Parapodia in general structure as in the male, but modified very differently in the anterior region. In this region the neurocirri are attached on the ventral side near the base; on the first parapodia they are relatively and actually thicker and longer than on the others, not flattened; decreasing gradually caudad until they are very slender and fall much short of attaining the end of the nem-o- podium, whereas in the anterior ones they equal that ramus. The notocu-ri of the most anterior parapodia are stout and conspicuously long, extending much beyond the notopodium; each narrows rather abruptly distally into a slenderly cyUndrical, distally pointed tip. Caudad the notocu-ri become smaller, as a 226 THE ANNELIDA POLYCHAETA. whole subulate, with no abrupt contrast between proximal and distal halves. The most anterior parapodia are very short in comparison with their height. They increase in length and stoutness caudad, those in the posterior portion of the anterior division being unusually thick and distended with ova. The neuropodimn has one distinct hgula, the notopodium two. These in the first few pairs are slender, but soon become thick and blunt. In the heteronereis division the parapodia are longer and much thinner and flatter in the cephalo- caudal direction, with the ova extending into them not at all or only an occasional one or two in the extreme base. Aside from the transformation of the setae mto the larger paddle-formed swimming type, these parapocha are conspicuously different in then- thin, membranous or foliaceous appendages, which in general are like those of the male. The acicula and setae are essentially as in the female. The tips of the longer anterior setae seem to be, as a rule, less prolonged. (Plate 30, fig. 5-8; Plate 31, fig. 10). The maxillae are larger and broader than in the male. Each is curved ventrad as well as mesad. Distally comparatively wide and blunt. The mesal edge armed with seven to ten low obtuse teeth, which at the chstal end of the series may appear as but slight undulations of the edge. (Plate 31, fig. 3). Localities. Ellice Island: Funafuti. Surface of lagoon, at 8 p. m. 24 December, 1899. Five females and thirty males. Gilbert Islands: off Ai'hno reef . Surface by night hght. 2 1 , 24 January , 1900. One male on the former date, and five niales and one female on the latter. While the two sexes of this species are very similar in general color, in the fine purpUsh markings, and in general appearance, as well as in the structure of the setae and the armature of the proboscis, they present very striking second- ary differences in various other structiual details. The prostomia are ahke in having the characteristic transparent preocular lobe; but in the male it is greatly longer, with the tentacles veiy much shorter and the palpi conspicuously modified. The differences in the nmnber of somites in the nereid cUvision and in the structure of the parapodia, particularly of the cirri, are marked. The structui'e of the natatory setae, as well as of the simple notopodials, and the form of the prostomium and its structures seem to be especially characteristic in this species. PSEUDONEREIS ' 227 Perinereis Kinberg. Ofvers. K. vet. akad. Forh., 186.5, no. 4, p. 175; St. Joseph, Ann. sci. nat., 1S97, ser. .5, 8, p. 2S.5; Gr.wier, Nouv. arch. Mus. hist, nat., 1901, ser. 4, 3, p. 155. Lipephile Malmgren, Annulata Polychaeta, 1S67, p. 50. Stratonice Malmgren, Op. cit., 1867, p. 56. Hedijle Malmgren, Op. cit., 1867, p. 58 (cpitokous form). Perinereis helleri Grube. Plate 35, fig. 8. Nereis (Perinereis) helleri Grtjbe, Annuiata Semperiana, 1878, p. 81. Tliis species has a close resemblance to P. cultrifera Grube occurring on the coasts of Europe. The specimens represented in the present collection agree essentially with Grube's description of the type of helleri, which is from the Philippines, as far as it goes. The teeth of the maxiUae are distally blunt or subacute, clearly less acute than in cultrifera. The paragnatha in gi-oup V are three in number, conical, arranged in a triangle. There is a single, lameUiform transverse tooth in VI . In I are two small conical teeth, one behind the other. In II there is a group of small conical teeth, few in niunber (seven to ten). In III there is a transverse patch of about ten teeth, usually in thi-ee transverse rows, with on each side of this patch and at some distance from it a characteristic group of two teeth one belund the other. In IV there are fourteen or more teeth in a triangular patch, with at its anterior apex often two teeth considerably smaller than the others. The anterior eyes are decidedly farther apart than the posterior ones, in this not agreeing with Grube's statement as to helleri. Localities. Paumotu Islands: Makemo. Reef flat. 20 October, 1899. Anterior ends of two specimens. Easter Island. Shore. 20 December, 1904. Several specimens. PsEtTDONEREis Kinberg. Ofvers. K. vet. akad. Forh., 1865, no. 4, p. 174. Paranereis Kinberg, Op. cit., 1865. p. 175. Naumachiits Kinberg, Op. cit., 1865, p. 17G. 228 • THE ANNELIDA POLYCHAETA. PSEUDONEREIS ATOPODON, Sp. noV.^ Plate 35, fig. 3-5. Consisting of from eighty-eight to one hundred and five parapodia-bearing somites. Lengtli of type 85 mm. Greatest width, which is in the region of the fifth somite, 3 mm., exclusive of the parapodia. One paratype has a width of 4 mm. in this same region. Back of the region of greatest width the body rapidly narrows and the dorsum becomes correspondingly lower. Prostomium as long as greatest width across base, or very nearly so. Pre- ocular portion bulging laterad at base, where as wide or slightly wider than width across anterior eyes; anteriorly widely and evenly semicircularly rounded. Posterior eyes at caudal edge as usual; large and somewhat obliquely subellip- tic. Anterior eyes a little farther apart than the posterior. Tentacles rather stout at base, conical, distally slender; nearly contiguous at base; fully four fifths or more as long as the prostomium and extending much beyond tips of the palpi. Palpi relatively very thick but proportionately short; distal article abruptly narrower than the first, but still relatively broad, distally subtruncate. Peristomium along median dorsal Une but Uttle more than half as long as the prostomium; laterally four fifths as long. Tentacular cirri short. Pos- terior dorsals reaching to the fifth parapodia-bearing somite; anterior dorsals reaching the second; ventrals a Uttle shorter than the anterior dorsals, subequal to each other. Parapodia all of moderate length. Both notopodial and nem-opodial setae occurring in all parapodia, excepting those of the first two pairs. In the notopodia of the first two somites there is a single distally rounded lobe, from the dorsal side of which arises a cirrus greatly exceeding it in length. In the caudal region the dorsal lobe is more elongate and the cirrus arises almost directly from its end, which appears as a slight rounded eminence at one side of the base of the long and slenderly acuminate cirrus. In the second and succeeding segments a second notopodial lobe is present between which and the cirriferous lobe the setae arise. In the neuropodia throughout there are two lobes, a ventral one bearing a cirrus much shorter than the dorsal one, in the anterior region a little exceeding its lobe, but as usual becoming shorter caudad and a second stouter setigerous lobe, the distal end of which may appear weakly bilobed. (Plate 35, fig. 3). ' oTOjTos, str.ange, and ASiic, tooth. LEODICIDAE. 229 The setae of the notopoclia are all of the ordinary slender type. In all neuropodia there are in addition much stouter setae, with shorter blades. In the setae of the stouter type the shaft is weakly curved; the socket is very obUque; the blade is small, conspicuously concave on the side on which the higher edge of the socket occurs, in the ordinary setae the sockets are homo- gomphous; the blade is long and distally capillary. (Plate 35, fig. 4, 5). Paragnatha weU developed on both basal and maxillary rings. V with a single transversely elongate tooth or lamella ; VI with a larger transverse lamella which is more or less divided into two parts; VII and VIII with teeth in a double transverse row, these teeth conical and somewhat flattened. The teeth in IV are in five or six closely ordered transverse rows, and are cognate at base in each series (pectinate). The teeth are similarly pectinate in four series in II. Teeth of I and III uncertain. The body in general is a somewhat dilute and nearly uniform brownish. The tips of the parapodial lobes and the cirri are paler. Locality. Tonga Islands: Nomuka. Taken on beach rock. 2 December, 1899. Four specunens. Especially distinctive of this species is the presence on the proboscis in I of a distinctly lamelliform transverse tooth, or plate, together with the numerous seriate or pectinate teeth in II and III. It has resemblances to P. galapagensis (Kinberg). Leodicidae. In this large family the body is long and more or less cylindrical, and is composed of numerous, essentially similar, short somites. The integument is smooth and commonly iridescent. The prostomium is distinct. It bears a pair of palpi. The number of ten- tacles varies from one to five, but frontal tentacles are never present. They are either subulate or may be very elongate distad of the basal region; a ceratophore often distinct, and the style may be smooth or more or less annulated. Eyes two or none. Nuchal organs in the form of cihated grooves. The peristomium is biannulate and may or may not bear a pair of nuchal tentacular cirri upon the second annulus. The parapodia are uniramous. Each bears a dorsal and a ventral cirrus. A certain number of the notocirri may bear branchiae. The branchiae may be simple filaments or more or less highly branched. Sometimes they are rudimentary and may be whoUy'absent. 230 THE ANNELIDA POLYCHAETA. Normally both simple and compound setae are present. The simple setae are of various types, a characteristic form among the ordinary ones being a very deUcate type with fine stalk and expanded terminal part distally pectinate. The compound setae have the terminal piece hooked or dentate, with membran- ous shields over the teeth. In the middle and posterior region uncinate spines or crochets occur. Anal cirri two or four. The neplu-idia have large, open, internal funnels through which in ordinary forms the sex products find exit. The proboscis is always armed with a powerful and complex system of horny or partly calcareous plates or jaws. Of these there is ventrally a pair of man- dibles and in addition seven or nine maxillae, the odd plate being normally on the left side. A distinct sexual dimorphism exists in some species, such as Leodice norve- gica and L. gigantea. A form of epitoky also occurs in some species, among which are the more conspicuous representatives of the palolo worms about which so much has been written, the best known of these being the Leodice viridis (Grube) of the South Seas. Typical epitoky, as seen for example in the Nereidae and Syllidae, is accompanied by a transformation in the parapodia and the development of special natatory setae in the sexual or epitokous division of the body. In the members of the present family these modifications do not occur. On the contrary, in the epitokous region the setae become much reduced in number and the somites undergo other special changes. At the time of sexual maturity the epitokous region becomes detached from the anterior end and, leav- ing the normal habitat, such as the cavities or burrows in coral reefs, rises to the surface and becomes pelagic. At the surface the sexual products are discharged. This swarming occurs at very definite times in relation to season and the phases of the moon. The habits of the Atlantic palolo, Leodice fucata, have been described by Mayer (Papers Tortugas lab., 1908, 1, p. 107, pi. 1). Cf. also Moore's observations on L. paloloides of the Californian Coast (Proc. Acad, nat. sci. Philad., 1909, p. 246). At the time of swarming the Atlantic Palolo turns about in its tunnels in the coral and limestone, detaches the sexual division, from which the products are discharged at the surface at sunrise, while the head-end regenerates the posterior end. In the same category is the "wawo", as known to the natives of the Malay archipelago, which is Lysidice oele, this form swarming on the second and third nights after full moon in March and April. {Cf. Horst, Mus. Haarlem Rumphius gedenkb. kolon., 1902, p. 105). LEODICIDAE. 231 Most of the leodicids secrete tubes of varied consistence, many of these being hyahne or papyraceous and composed exclusively of the secretion of the worm, while in other cases fragments of shells, frustules of diatoms, shells of Foraminifera and Radiolaria, tubules of serpuhds, fragments of sea-weeds, and other materials may be made use of in the construction of the walls. The tubes are commonly simple, but may be branched. The mucus forming the sub- stance or the matrix of the tubes is secreted by glands at the bases of the neuro- cirri of the anterior region. Some species inhabit cavities or burrows in rocks, calcareous Algae, coral reefs, or in the mud, the retreats being lined ordinarily with a thin layer of transparent material. They are frequent in all parts of the world, though apparently more abun- dant in the warmer seas. They occm* often between tide-marks or near low tide, in crevices of rocks, in mud, as among the growths of Zostera, among shells, or in madrepores. In removing them from their retreats autotomy is fre- quent. On the other hand some species may occiu- at depths approaching the thousand fathom mark, though they do not attain depths as great as in the closely related forms of the Onuphididae. Many species exhibit phosphorescence. Thus Crossland found Lysidice afra (Peters) to be strongly phosphorescent during removal from the mud, a blue light being given out from the mucus secreting pads adjacent to the neu- ropodia and the mucus itself remaining luminous. Key to Genera. a. Branchiae present. b. Tentacles and eyes none Iphitiine Marenzcller. 6b. Tentacles and eyes present or the latter indistinguishable, c. Tentacles five. d. Tentacular cirri present Leodice Savigny. dd. No tentacular cirri. e. Composite setae present Marphysa Quatrefages. ee. Setae all simple Aphelothrix, gen. nov.' cc. Tentacles three or less; tentacular cirri none. d. Tentacles three A mphiron Kinberg. dd. Tentacles two Coelobranchus Izuka. aa. Branchiae none. 6. Tentacles five. c. Tentacular cirri present Nicidion Kinberg. cc. No tentacular cirri Paramarphtjsa Ehlers. bb. Tentacles three or less; no tentacular cirri. c. Tentacles three Lysidice Savignj'. cc. Tentacle one Nematonereis Schmarda. ' Marphysa mossambica Peters, genotj-pe. d^eXijs, simple, and 0pi^, bristle. 232 THE ANNELIDA POLYCHAETA. Synonymy of Genera. Nauphanta, and Nausica Kinberg (1865) fall under Marphysa as does also MacDufRa Mcintosh. Blainvillea Quatrefages is synonymous with Nematonereis Schmarda. The position of Heteromarphysa Verrill is somewhat doubtful. It would fall with Nicidion in the key above, but according to Verrill's account differs from that genus in having the prostomium f\ised with the peristomium above and also with the second somite. Leodice Savigny. Descript. Egypte. Hist, nat., 1809 [= 1822], 1, pt. 3, p. 13, 48. Eunice Cuvieb, Regno anim., 1817, 2, p. 525; ed. 3, 1830, 3, p. 199; Quatrefages, Hist. nat. annelcs, 1865, 1, p. 307; Ehlers, Borstenwiirmer, 1868, p. 303. Nereidonta Bl^inville, Diet. sci. nat., 1828, 57, p. 475. Eriphyle Kinberg, Ofvers. K. vet. akad. Forh., 1865, no. 4, p. 561. Mayeria Verrill, Trans. Conn. acad. sci., 1900, 10, p. 650. The species of Leodice listed in this paper may be separated as follows: a. All branchiae simple, cirriform. 6. Tentacles strongly articulated, nearly moniliforin; branchiae beginning on somite IX; teeth of maxillae II six or seven L. makemoana, sp. nov. 6b. Tentacles not obviously articulated; branchiae beginning in middle region of body; teeth of maxillae II two (or three) L. siciliensis Grube. aa. Branchiae, in part at least, branched. b. Tentacles smooth throughout, not distinctly articulated. c. First branchiae occurring on somite V, the last on or near somite XLIII. . . L. scgregata, sp. nov. cc. First branchiae on somite IX or farther caudad. d. First branchiae on somite X\TI or XVIII, the last on or near somite CXII . . . .L. liia, sp. nov. dd. First branchiae on somite IX, and occurring on all subsequent ones excepting last two or three L. contingcns, sp. nov. 66. Tentacles distinctly annulate. c. Branchiae beginning on somite VII. d. Branchiae at most with two or three branches, these rather arbuscular, but mostly simple and cirriform. e. Branchiae all .shorter than the notocirri; branched branchiae beginning with the fourth. L. oliga papeetensis, subsp. nov. ee. Branchiae in widest part of body decidedly longer than the notocirri; branched branchiae beginning with the second L. oliga, sp. nov. dd. Brancliiae in part with five to seven filaments and most with more than three, the branchiae unilaterally pectinate L. panamena, sp. nov. cc. Branchiae beginning on somite IX or X. d. Branchiae beginning on somite X; filaments arbuscular in arrangement, at most four in number; tentacles articulate only distally L. pauroneurata, sp. nov. dd. Branchiae beginning on somite IX; unilaterally pectinate, with filaments numerous, exceed- ing ten on some branchiae; tentacles articulate proximaUy L. nesiotes, sp. nov. LEODICE MAKEMOANA. 233 LeODICE MAKEMOANA, Sp. nOV. Plate 53, fig. 1-11. The type is gi-eyish yellow throughout, the only markings being a longitudi- nal series of small, transversely elongate, whitish spots over the middle region of the dorsum, a single spot occm-ring on each somite, and a midventral white stripe. The appendages are but slightly paler than the body. From the region of the seventeenth and adjacent somites the body narrows conspicuously cephalad but only slightly caudad, remaining of nearly uniform width to the extreme caudal region where it narrows strongly to the pygidimn. The total length of the type is only 20 mm. The greatest width, exclusive of parapodia, is 1.8 mm. The total number of somites is ninety-four. The prostomium appears a little shorter than the peristomium. It is bilobed as usual, a wide, rounded furrow extending down its anterior face. Each lobe curves outward and caudad and is but weakly subdivided by a cross-furrow. Its surface is very smooth. The tentacles are arranged in a transverse row con- tiguous with the margin of the peristomium excepting the outer paired ones which are inserted at the side farther forward. The tentacles are all distinctly jointed and almost moniliform, the articles being very short and rounded. The median tentacle, the tip of which is apparently broken off at point, consists of sixteen articles and reaches the seventh sonaite. Each inner paired tentacle consists of fourteen articles, or close to that number, and reaches the fourth somite. Each outer paired tentacle is constricted toward base, and is very short, consisting of six (or seven) articles and not quite reaching the second somite. The eyes are black, broadly elhptic areas, caudad of each outer tentacle, and partly covered by the peristomium. (Plate 53, fig. 1). The peristomium dorsally is shorter than the three succeeding somites, and the anterior margin is a little incurved mesally opposite the median ten- tacle and the siuface is wholly smooth. Laterally there is on each side a sub- longitudinal fmTow extending from an incision in the anterior margin, the surface above the furrow crossed by a few subvertical wrinkles; from the ante- rior end of the furrow a weaker furrow extends caudomesad, setting oiJ the lower lip. The surface of the lower lip is smooth. Its anterior margin at the middle curves deeply and semicircularly caudad. The second somite is distinct above and below, but at the sides is fused with the first somite. It is shorter than the third somite. The cirri are very small, 234 THE ANNELIDA POLYCHAETA. pale, distally tapered processes extending but little beyond the middle of the peristomium. They seem but vaguely and partially annulate. (Plate 53, fig. 1). The third and succeeding or parapodia-bearing somites are regular and undivided. They are rather short, in the widest part of the body being eight times wider than long. The dorsum is strongly convexly arched in the usual way, a little depressed along the middorsal line and along each side toward the para- podia. The anterior somites show a few weak longitudinal impressed lines. The venter is flat; a weak vertical fiurow is traceable except anteriorly and posteriorly, the furrow more distinct over middle and caudal portions. The pygidium is very short, slightly narrowed caudad and broadly obliquely truncate, the anus being subdorsal in position. There are- two anal cirri scarcely exceeding a mm. in length, pale, gradually tapered and annulate, the annuli short and not strongly marked; and in addition there are two more ventral cirri, these being relatively minute and also indistinctly shortly annulate, one inserted at base of each larger one on its ventral side. The parapodia are processes of moderate length, distally more or less rovmded, and having a shghtly elliptical cross-section, the long diameter being vertical, so that the parapodia appear somewhat compressed in an antero- caudal direction, the most anterior ones, however, being more strictly cylindri- cal, aU narrowing distad. The first parapodium on each side is noticeably reduced. The dorsal cirri arise from the bases of the parapodia. Each is a moderately slender process thickest at base and gradually tapering to the nar- rowly rounded distal end; it is annulate, the annuli being very short and usually not strongly marked, or sometimes even vague. In the anterior region the notocirri decidedly exceed the parapodia and setae; caudad they become more slender and shorter. The ventral curi in the anterior region consist of a cylindri- cal, proximal article and a much shorter, abruptly narrower, distal article which is a Uttle narrowed distad and has the distal end rounded. The neurocirri of the region a little exceed the parapodia. In the posterior region the neurocirri are, as a whole, much less stout, conical processes, and toward the caudal end have become markedly slender, mth the apical portion long, thin, and uniform in diameter, subfilamentous. In all parts the neurocirri remain longer than the parapodia. The branchiae begin on the ninth somite (seventh parapodial) and occur on all subsequent somites excepting the last six. The branchiae consist in all cases of a single, slender, wholly unbranched filament. The filament is slightly tapered from the base to a narrowly rounded extremity. The first branchia LEODICE MAKEMOANA. 235 exceeds its notocirrus onlj- a little, but the following ones rapidly increase in length and soon greatly exceed the cirri, in the wddest region of the body fall- ing but httle short of attaining the middorsal line. From tliis region caudad they again rapidly decrease in length, but they remain of nearlj- uniform length in the middle and posterior region where they extend but about half way to the middorsal line. The branchiae of the last three pairs rapidly decrease, the last ones being but slight inadiments. (Plate 53, fig. 7-11). The acicula proper are two in number in each parapodium, the tips visibly projecting on parapodia from the second inclusive caudad. They are pale in color, the posterior ones scarcely darker than the fu-st ones. The hind portion of each is straight, sUghtly narrowing distad; the short projecting tip is slightly curved, and subventrally directed. The crochets first appear on or near the twenty eighth parapodia, projecting a shorter distance in anterior part of series than in the posterior. Each crochet is in the distal half curved first greatly cephalad and then a little caudad. The head may bear either two teeth, or a reduced, supplementaiy, tliird tooth is more frequently present on caudal side of the apical one. The apical tooth is a little curved forwards, the small one at its base bemg vertical. The supplementary' tooth is much stouter and longer and stands either nearly at right angles to the axis or, in posterior region, it is more commonly considerably reflexed proximad. The guards extend out over the subapical tooth and rise to a httle above the level of the apical one. (Plate 53, fig. 6). The compound setae form a ventral group of usually thi-ee or four. The shafts of these are long, gently curved, with the convexity cephalad, of uniform diameter to near the distal end where clavately enlarged, the enlargetl portion unusually short. The appendage is a small narrow piece ending above in a long, curved, terminal tooth; below this is a very small, subapical tooth; below the subapical tooth the piece widens to an obtuse process, with upper edge horizontal for a short distance from apex, leaving a very small tooth. The guard is narrow, its free edge weakly concave. (Plate 53, fig. 5). The capillary setae of the dorsal fascia much exceed the other setae in length ; they are distally slenderly acmninate, being drawn out to a very' fine tip; they are usually dis- tally cur^'ed. The pectinate setae have the usual general structure. The distal piece is proportionately broader and shorter than the average. The teeth increase in length from one edge to the other, at which there is a much longer process. (Plate 53, fig. 4). The maxillae are pale and small. Maxillae I have the united carriers form- ing a plate somewhat shield-shaped; the caudal end rounded and mostly shal- 236 THE ANNELIDA POLYCHAETA. lowly incurved, the sides convex caudally, concave toward anterior end, with the greatest width across anterior end; anterior margin forming a very obtuse reentrant angle; plate black along anterior margin and down the median line. The blade is of the usual general shape. (Plate 53, fig. 3). Maxillae II with six large teeth on the left piece, seven on the right. Maxillae III with the right piece strongly, almost semicircularly, bent; bearing eleven (or twelve?) smaller teeth; the left paired piece less strongly curved, with eight teeth, the unpaired piece also apparently with eight somewhat smaller and paler teeth. The mandi- bles are nearly uniform whitish throughout. The anterior margin of the mastica- tory plate is little, very obtusely angularly, incurved, but not dentate; the outer edge is a little incised. The surface of the plates is finely striate, the stems are broadly united anteriorly. They are straight, each broad at the anterior end and narrowing conspicuously caudad. (Plate 53, fig. 2). Locality. Pamnotu Islands: Makemo. 21 October, 1899. One specimen. While there might seem the possibiUty that this may be the young of a previously described species, this is very improbable in view of the highly dis- tinctive combination of characters it presents, and especially of the fact that the specimen contains well-developed eggs. The presence of branchiae as wholly simple filaments on all but the first six and last six pairs of parapodia, the strongly jointed, submoniliform tentacles, the extremely short tentacular cirri, the annulate notocirri, and anal cirri, the essentially tridentate crochets, and the form and dentition of the mouth-parts would seem clearly to establish this speci- men as the type of a very distinct species. Leodice siciliensis (Grube). Eunice siciliensJs Grube, Actin. echinod. wiirmer Mittelmeeres, 1840, p. S3; Arcliiv. naturg., 1851, 17, p. 41; Ehlers, Borstenwurmer, 1864, p. 353, pi. 16, fig. 1-7; Grubb, Annulata Semperiana, 1878, p. 161; Gravier, Nouv. aroh. Mus. hist, nat., 1900, ser. 4, 2, p. 261; Crossland, Marine fauna Zanzib. & Brit. E. Africa. Polychaeta, 1903, 3, p. 323, pi. 22, fig. 8, 9; Atjgener, Fauna Sudw.-Austr. Polych., 1, 1913, 4, p. 279. Eunice adriatica Schmarda, Neue wirbellose thiere, ISiJl, 1, pt. 2, p. 124, pi. 32, f. 257. Eunice taeyiia CLAPARfeDE, Mem. Soc. phys. hirt. nat. Geneve, 1864, 17, p. 120, pi. 4, fig. 11; Annelidas Chetop. Golfe Naple.s, 1868, p. 135. Eunice ebranchiata Qu.\trefages, Hist. nat. aniiel6s, 1865, 1, p. 316. Eunice bitorqitata Grube, Jahresb. Schlesch. gesellsch., 1869, 49, p. 28. Eunice leucodon Ehlers, Zool. jahrb. Suppl., 1901, 2, p. 261; Festsch. K. gesellsch. Gottingen, 1901, p. 128, pi. 16, fig.1-10. A single, unusually long specimen broken into two pieces is in the collection. The body in general is greyish brown, in some parts of a more or less rusty tinge. LEODICE SEGREGATA. 237 The total length is near 330 mm. with a maximum width of 3.5 mm. The total nmnber of somites is in the neighborhood of seven hundred. The first branchia detected was near somite CCCXV. The mandibles project prominently as usual; each is white along the ectal border and in a narro\ving stripe along the anterior edge, being elsewhere dilute brown. The maxillae are black, not edged with white as in leucodon Ehlers, with the teeth typical. The antennae are of moderate length but decidedly longer than represented by Ehlers for his leucodon, the types of which were taken at Juan Fernandez. The structure of the setae seems to be typical. This species, which is very closely allied to the famous palolo worm (L. viridis), has an exceptionally wide distribution, having been previously recorded from the Mediterranean, Madeira Island, West Indies (Porto Rico), Juan Fernandez Island, Philippines, Austraha, East Africa, Gulf of Persia, and Red Sea. Locality. Off Panama: TaboguUla Island. 31 October, 1904. One specimen taken on the shore. LeODICE SEGREGATA, Sp. nov.^ Plate 54, fig. 1-5. Type incomplete; about 114 mm. long; maximum width of body, 7.1 mm. Number of segments in the incomplete specimen one hundred and eighteen. Prostomium broad, deeply sunken in peristomial collar to bases of tentacles, anteriorly deeply incised and bilobed to form the thick, bluntly rounded palpi. Each palp divided by a shallow transverse groove into a more prominent ventral and a smaller dorsal lobe. Tentacles in a transverse row in which the two laterals on each side are close together but not contiguous, the median separated from the nearest lateral on each side by a wider space. Tentacles smooth tliroughout, not at all annulated or articulated and with no distinct ceratophore. Median tentacle reaching to somite VII; outer paired tentacles much stouter, reaching only somite II. Peristomium large, equalling in length the two and one half succeeding somites; on each side weakly longitudinally furrowed, below the furrow the prominent, thickened lower lip which is crossed longitudinally by a number of impressed Unes or sulci, but the free edge of Up not crenulated, mesally straight. ' segregare, to separate. 238 THE ANNELIDA POLYCHAETA. Somite II apodous as usual, coalesced with I at the sides. Nuchal cirri more slender than tentacles, like which they are smooth, subulate, reaching to near middle of prostomium. The succeeding somites bearing parapodia, regular, undivided; at widest part of body about seven to eight times as wide as long, posteriorly only four to five times wider than long. Strongly arched above, ventrally slightly arched, with deep median longitudinal neural groove. The greatest width is attained in the region of somite XXV, from whence the body width is nearly uniform to near somite XL, following which it gradually decreases. Parapodia simple rounded processes of the form and arrangement usual in the genus. Notocirri conspicuous, proximally stout, distally strongly tapered, subulate; posteriorly more slender, as usual. Neurocirri anteriorly with large, conspicuously swollen, bases of elliptic outline on each of wluch is borne a very short, abruptly greatly thinner style; posteriorly the base is less swollen and finally passes gradually into the style, the whole cirrus being somewhat subconical; short, but httle exceeding the parapodium. Branchiae beginning on somite V, on which each branchia is a simple slender filament. The branchia of somite VI has a single branch; on somite VII the branches are abruptly more numerous, reaching ten; on subsequent somites the branchiae acquire branches increasing in number and length ; the stem typi- cally stout, distally acuminate, pigmented and presenting an annulated appear- ance, arising from base of notocirrus; filaments unilateral in arrangement, or occasionally with one small branch inserted on opposite side distally, on branchia of twenty eighth somite, near twenty-one in number. The filaments decrease again in number caudad, the last branchiae, which occur on somite XLIII, having but two filaments each. The brancliiae are long, much exceeding the middle of dorsum excepting at ends of branchiate region, the dense tufts of fila- ments largely concealing the dorsum. In a paratype from Sta. 3417 the first branchiae, i.e., those of somite V, have numerous branches, but on posterior somites the number gi'adually decreases. In paratj^jes branchiae may occur as far back as the sixtieth somite. (Plate 54, fig. 4, 5). The acicula are yellow with the central fibrillae darker. They are stout, distally acuminate and slightly curved distally; medulla conspicuously fibrU- late; they are mostly two in number. Anteriorly they scarcely protrude from the tubercle, but on the posterior segments they protrude conspicuously. The setae are nearly colorless, being of a weak yellowish tinge. They are of the usual four kinds. A dorsal tuft arising in connection with the acicula is composed LEODICE SEGREGATA. 239 of rather numerous, slender, colorless, simple capillar>^ setae. These appear flattened, distally slenderly pointed, and straight or slightly curved. Among the capillary" setae are the shorter deUcate pectinate setae; each of these presents the usual clavately expanded distal end which is finely toothed along its free edge and at one angle bears the usual marginal process which may be conspicu- ously curved outward, but is often straight. (Plate 54, fig. 2). Below these are the compound setae; these are stouter than the capillary setae; they are pale yellow in color; each is composed of a shaft, which is straight or nearly so, and is moderately enlarged distad, and of a bidentate appendage covered as usual by a delicate guard. On the middle and posterior segments crochets appear; these are stout, distally naiTowed and moderately curved; the principal tooth of each is very stout and at its tip is sUghtly curved toward axis; the usual terminal tooth is slightly cm'\'ed toward the other tooth; its tip is about on a level with that of the principal one. (Plate 54, fig. 3). Masticatory plates of mancUbles hard, white, their anterior edge wa\-y and the ectal angle acutely produced; stems of mandibles blackish, stout, straight, and a httle divergent ; the halves firmly united anteriorly by an isthmus. Maxil- lae I (forceps- jaws) with basal pieces, or carriers, longer than wide; each wdth outer edge nearly straight and subparallel to inner edge, ectocaudal angle widely rounded and the caudal edge within rounded portion straight, the ectocephalic angle curved ectocephalad; the forceps stout, falcate in form, as usual, black- ish. MaxUlae II strongly chitinized, black; left outer plate with seven large teeth. The unpaired piece with ten much smaller teeth. Structm'e of other pieces not determined in type. In a paratype from Sta. 3417 the left plates of Maxillae II have respectively eight and ten (eleven) teeth, the right piece nine teeth; maxillae III have nine teeth. (Plate 54, fig. 1). Color in general dark brown, but the dorsum with a conspicuously contrast- ing, paler, yellow band along each side above parapodia, the parapodia and con- tiguous parts, including the cirri and branchiae, being of the same lighter color; the dorsum anteriorly and much of the venter has a reddish cast to the brown, but caudally the color becomes somewhat fen-uginous. Locality. Off Panama: Sta. 3354 (lat. 7° 9' 45" N., long. 80° 34' W.). Depth 322 fms. Bottom of gi-een mud. Bottom temp. 39° F. 23 February, 1891. One specimen. Off Panama: Sta. 3358 (lat. 6° 30' N., long. 81° 44' W.). Depth 555 fms. Bottom of green sand. Bottom temp. 40.2° F. 24 February, 1891 . One specimen. Off Mexico: Sta. 3417 (lat. 16° 32' N., long. 99° 48' W.). Depth 493 fms. 240 THE ANNELIDA POLYCHAETA. Bottom of green mud. Bottom temp. 40.6° F. 11 April, 1891. Two speci- mens. This species in structure seems to approach Leodice indica (Kinberg) (L. congesta (Marenzeller)) closely. The gills have nearly the same structure and distribution, excepting that in the present species they begin farther forward (somite V) than usual in indica (usually somites VII to X, but rarely farther forward). The anterior apodous somites and the tentacles and cirri of the two species are very similar excepting in a few points, such as that the inner lateral tentacles are relatively longer. The present species, however, is a much larger and more robust form, with a strongly marked color-pattern which indica lacks. The jaws are larger and coarser; the carriers of the forceps are more uniform in width, not bulging caudally ; the parts of maxillae II on the left side have more numerous teeth, with those of the outer piece stouter and seven in number as against ten on the inner, whereas in indica the numbers are more nearly equal in size and number (six and seven respectively in Marenzeller's type). The cro- chets seem also to cUfTer in the form and direction of the teeth. Leodice lita, sp. nov.^ Plate 54, fig. 6-10; Plate 55, fig. 1-7. The general color is dull greyish brown, uniform above. Ventrally there are in the anterior region, but not in the median and posterior, three distinct longitudinal white stripes of which the median is fully twice as wide as the lateral ; each lateral stripe runs close to the bases of the neurocirri. The tentacles, parapodia, and cirri are lighter than the body, but the contrast is not strong. The body from the region about somite XII narrows, strongly cephalad and more gradually caudad, behind the branchial region becoming much more slender, the caudal end rather abruptly subacute. Length about 80 mm., the hardened and much coiled condition of the type making wholly precise measure- ment difficult. Greatest width, exclusive of parapodia, 4 mm. Total number of somites near two hundred and forty-two. The sexual region lies caudad of the first one hundred and ten somites. The prostomium is of moderate length, nearly equalling the peristomium. It is divided in front as usual by a vertical median incision. Each lobe is trans- verse, with inner end thickest and surface but httle uneven. The tentacles are arranged in a weakly curved transverse series with their bases in contact with ' Xiros, simiile. LEODICE LITA. 241 the peristomium, or partly covered by the latter. There is a distinct short ceratophore, but otherwise the tentacles seem to be wholly unjointed, smooth. All are broken off distally. The peristomium in length about equals the succeeding three somites. Dorsally the anterior margin bulges forward convexly at the middle. The surface is finely longitudinally wTinkled. The anterior margin on each side is notched, a furrow extending from each notch with a branch extending caudo- ventrad and one strictly ventrad, the border elevated in front of the latter. The ventral portion or lower lip is wholly smooth, with its anterior margin deeply concave and entire. The second somite is exceedingly short. It is distinct not only above and below, as usual, but also laterally, where it extends forward in a small triangular area. The cirri are smooth, subulate. They extend forward nearly to the anterior margin of the prostomium. The somites from the third caudad bear parapodia. They are regular and undivided. They are v£ry short, in the widest part of the body (near somite XV) being nearly sixteen times wider than long. Dorsally the anterior somites are strongly arched, the body here being deepest, while in the anterior portion of the branchial region they are depressed, again becoming more convex farther caudad. There is no trace of a median longitudinal fmTow in the anterior somites, but in the branchial region one appears, at first wide and shallow and then sharply and narrowly impressed in the posterior sexual region. The somites from the second caudad to the midbranchial region are crossed by numerous longitudinal sulci, these disappearing from the middorsal region on the more posterior ones. Ventrally the somites are but weakly convex ; there is the usual neural furrow which is wider and shallow anteriorly, in tLc Lranchial region becoming narrower and deeper like the corresponding dorsal furrow and fading out in the caudal region. Pygidium small ; anus subdorsal. Anal cirri missing from type. On the anterior somites the parapodia are prominent, distally rounded processes; but they soon become reduced and but slightly elevated. The notocirri arise high on the sides of the somites above the fascicles of setae. Anteriorly they are proximally stout, narrowing distad, and rather long, extend- ing beyond the setae; caudad they become shorter and more slender and before the end of the branchial series is reached, they are reduced to pale, subu- late processes minute in comparison with the branchiae ; caudad of the branchial series they continue to the end as unusually fine, short filaments. The first 242 THE ANNELIDA POLYCHAETA. neurocirrus, that is, the one of the third somite, is a short, stout, subconical process; and the second and third are intermediate between the first and the fourth; the fourth and immediately succeeding ones are long, cylindrical processes bearing apically a much smaller, irregularly conical lobe; this general form is retained toward the caudal region, but the cirri become shorter and shorter and are often constricted proximally ; in the posterior region they again take on the conical form without distinction of a distal lobe, finally becoming very small and almost obliterated. The typical acicula, as occurring throughout except in the most anterior region, are black, stout, straight, excepting for a slight curve distally, with the acute tip projecting among the bases of the setae, as usual. Only one aciculum occurs in each parapoclium. The dorsal acicula are represented, in the anterior region at least, by a small fascicle of fine pale fibers extending into the base of the notocuTus. The first true aciculum that could be detected by surface examination is in somite XXV, in which the first crochet also occiu-s. The setae are of the usual four types. The crochets occur first on or near the twenty fifth somite. Each crochet is veiy dark, blackish, excepting the colorless, nearly transparent tip. The shaft widens conspicuously distad half- way to the tip and then narrows to the teeth. Each is weakly doubly curved and bidentate, with the tips of the teeth directed caudad. The subapical tooth is large, straight, and acute. The apical tooth is very much smaller, being minute, nearly erect, and but shghtly curved caudad. The transparent mem- branous guards extend over the teeth, rising convexly between the two and usually distinctly above the level of the apical one. (Plate 55, fig. 5). The compound setae of each parapodium form a separate ventral fascicle, as usual. They are coarse, with the shaft proximally cylindrical and of uniform diameter, but at the upper end suddenly strongly clavately widened. The appendage is distally bidentate. The apical tooth is long and rather slender, proximally erect and distally strongly curved or hooked; the subapical tooth is much smaller and is straight, relatively thick at base. The edge of the membranous guard is weakly convex between the subapical tooth and the subbasal angle; it does not rise above the apical tooth. (Plate 55, fig. 6) . The setae of the dorsal fascicle are strictly capillary; no limbi or wings are detectable; long, tapering, finely tipped, the tip often curved, especially in the smaller ones. Among the capillary setae are the pectinate setae. These have the usual general form. The cuneate appendage is concave from side to side. At one end of the distal series of teeth is noraially a much longer, lash-like process, or fiagellum. (Plate 55, fig. 7). LEODICE LITA. 243 The first branchia on the right side occurs on somite XVII, that of the left side on somite XVIII. They cease at or very near somite CXII, the somite not being determinable with certainty in the type. The first branchia is a short, slenderly conical, or subulate, simple process arising dorsally from the base of the notocirrus, which greatly exceeds it. Those immediately succeeding in- crease progressively in length, becoming more filament-like, and the sixth and succeeding ones exceeding the notocirri, in the posterior part of the series greatly so. The anterior branchiae are all simple filaments; the twelfth and thirteenth bifurcate below the middle; some of the immediately following ones are again simple, but most are bifid, the branching occurring closer to the base, while in the posterior portion of the series all are simple filaments again. (Plate 54, fig. 6-10; Plate 55, fig. 1). The first pair of maxillae are tliin and pale. The carriers are proportion- ately elongate and narrow; the piece formed by the two of them is narrowest at the anterior end where the sides are nearly parallel, the caudal region on each side moderately convexly bulging; an acute median incision between the halves caudally. The blades proportionately to the carriers are broad, pro- jecting on each side widely beyond the outer edge of the latter. Each has the general sickle-shape usual in the genus. (Plate 55, fig. 3). Maxillae II are also pale. The outer edge of each is bent upward and is a little reflexed at the extreme caudal angle, the elevated portion short, narrowing and disappearing rapidly cephalad. The caudal margin deeply excavated between the outer elevated angle and the inner caudal process, the outer angle projecting caudad nearly as far as the inner process. On the left one there are four stout, distally rounded teeth, on the right five, the teeth on each occupying a space decidedly shorter than the smooth edge proximad of them. The left paired plate of maxillae III bears seven small teeth, the right one eleven. The unpaired plate bears four (or five) teeth. The structure of maxillae IV was not made out clearly. The mandibles are pale throughout excepting the outer border of each masticatory plate, which is blackish. Each masticatory plate is broadly oblong in outUne, a little bent caudad and with the angles rounded; the edges are wholly smooth, having neither processes nor incisions; the two meet at an acute angle in the middle. The stems, anteriorly as wide as the plates, narrow gradu- ally and strongly caudad, the caudal portions curving away from each other. (Plate 55, fig. 2). Locality. Marshall Islands. A single specimen came up on the anchor from a depth of 12 fms. Albatross Exped. 1899-1900. 244 THE ANNELIDA POLYCHAETA. This species seems to be rather widely separated from the other Pacific forms in the character and arrangement of the brancliiae, e.g., in having the branchiae either simple or at most with two filaments, with the first one appear- ing far back (somites XVII-XVIII) and the series terminating near the middle of the length. Among the Pacific forms the species suggests L. paupera (Grube) in the weak development of the branchiae. In the latter species, however, the branchiae begin on the twenty fifth somite (twenty third parapodial), are in part three-branched, and extend nearly to the caudal end of the body. In that form there are in each parapodium from the twenty fifth caudad two acicula and two crochets instead of one of each, the teeth of maxillae II and III are fewer, and the somites are fewer, — one hundred and twenty-seven as against two hun- dred and forty-two. Leodice oliga, sp. nov.^ Plate 55, fig. 11; Plate 56, fig. 2-9. Body in general duU brown, without markings; the tentacles lighter, somewhat yellowish; the cirri and branchiae but httle lighter than body, of greyish cast. The body is first slightly narrowed anteriorly, but it narrows moderately caudad from the region of about the fifteenth somite. It is unusually short, the total length of the type being nearly 16.5 mm. and the greatest width, exclu- sive of the parapodia, 2 nam. The total number of somites is eighty-two. Prostomium divided in front by a moderately deep and narrow vertical median incision; each lobe subpyriform, with the enlarged end ectoventrad in position, with on its anterior surface a curved, sublongitudinal furrow nearer outer side and with ends curved mesad. The median or inner paired tentacles are in contact with the peristomium; each outer paired tentacle is inserted close to the base of the corresponding inner one, in front and but little ectad. The tentacles are all distinctly jointed, the articles short and rounded and the ten- tacles in distal portion submoniliform. The median tentacle reaches to somite XVI; it narrows from the base distad to the slender distal portion and con- sists of twenty-nine or thirty articles. Each inner paired tentacle is in form hke the median but is much shorter, extending to the ninth somite and consisting of nearly twenty articles. Each outer paired tentacle is very short, reaching only ' oXLyoi, short, little. LEODICE OLIGA. 245 to the second or beginning of the third somite. It is thinner proximally than the other and is relatively less attenuated distad. It consists of eight articles. The peristomium is as long as the next three and a half somites. The dorsal surface is smooth, or essentially so, showing but a few fine punctae and some very fine curving impressed lines. The anterior margin above is straight or slightly indented at the middle; the sides are not incised and there is but a fine weak longi- tudinal sulcus crossing the peristomium on each side. From near the anterior margin on each side a wide furrow runs ventrad and then convexly mesocaudad, setting off an elevated anterior border and the median area or lower Up. The anterior margin of the lower lip is widely and not deeply concave. The second somite is distinct below and above but is fused laterally with the peristomium in the more common way. Each tentacular cirrus is a slender, tapered process extending about to the transverse sulcus in front of outer paired tentacle; it is strongly annulate, the articles being short, distinct, and eight in number. The third and succeeding somites are regular and undivided, though some of the anterior ones show above a weak transverse sulcus nearer the anterior margin than the caudal. The somites are very short, those in the widest region of the body being from ten to eleven times wider than long. Dorsally the somites are convexly arched and moderate in height; those of the posterior two tliirds of the body are crossed by a narrow, distinctly impressed, median, longitudinal sulcus. The venter is flat. It is crossed over the entire length by a narrow, very distinct, neural furrow. The pygidium is obUquely truncate above; below it narrows to an angular caudal point. The principal anal cirri are long and strongly segmented, the articles short, and eleven or twelve in number. The parapodia are moderate or short in length. They are compressed in the cephalocaudal direction, the more anterior ones less so, subcylindric in cross-section. In anterior or caudal view they narrow from the base distad to the subtruncate or weakly rounded setigerous apex, the upper side more obUque than the lower. The notocirri arise from the base of the parapodia above. Each is a slender, distally strongly acuminate process which is dis- tinctly segmented throughout, the articles short but always considerably longer than thick. They decrease in size caudad as usual. The neurocirri of the first few pairs are long and subcylindi-ical, narrowed moderately caudad and with the small distal article not abruptly set off; the following somites have the basal article stouter and more uniform, while the distal article is a,bruptly very 246 THE ANNELIDA POLYCHAETA. much more slender than the basal and relatively long, being about two thirds as long as the basal. In the middle region of the body the ventral cirri have become much reduced both in length and diameter and the Isasal article in particular has become relatively much smaller, each cirrus as a whole being a narrowly conical process, a form maintained to the caudal end of the body. The branchiae begin on the parapodia of the seventh somite and exist on all subsequent ones to the end of the body, though on the last two pairs they are almost obliterated. The first branchia consists of a single filament which is a little shorter than the notocirrus, from the base of which it arises. The second branchia is bifurcate, two filaments arising from a short common stalk; the filaments clearly exceed the notocirrus. The succeeding four branchiae are similar, each consisting of two slender equal filaments increasing in length caudad, the sixth branchia falling but little short of reaching the middorsal line. From the sixth the branchiae decrease again in length and become much reduced in the middle region where they do not reach halfway to the middorsal line, and then again increase in size caudad. The seventh branchia consists of three filaments, the extra one apparently formed by bifurcation of the more dorsal of the two filaments in a gill such as the preceding one, the third filament arising on the outside of the stalk at a level below the other two; the eighth, ninth, tenth, and eleventh are similar to the seventh, and the twelfth to eighteenth, inclusive, are again bifurcate. The following branchiae are again composed of single filaments, their simple branchiae occurring on all parapodia of the remaining and greater portion of the body excepting on seven or eight pairs preceding the last six or seven pairs, on which they are bifilamentous, the last ones being again simple. The last few branchiae are much reduced. (Plate 56, fig. 5-10). The acicula proper are pale in color ; the acuminate tips are narrowly rounded and project but moderately; those of each parapodium lying in rather close contact. The crochets extend obliquely through the parapodium and emerge close to the neurocirrus. They are easily broken off. They are rather stout and present the usual double curve in their free portion. Each is tridentate; there is a large conical subapical tooth at right angles to the axis and a much smaller apical tooth curved forwards and bearing well distad on its caudal side the minute third tooth or denticle. The membranous guard extends over the subapical tooth and rises angularly well above the level of the apical tooth. (Plate 51, fig. 11). The crochets begin on the twenty fifth somite or a somite adjacent to it. The setae of the dorsal group are strictly capillary and non- LEODICE OLIGA. 247 limbate; they are distally finely pointed and the apical portion is often curved. The compound ventral setae are very much coarser than the capillary ones and than the corresponding ones in E. makemoana. The shaft of each is long and cxirved and at the end abruptly clavately widened as in makemoana. The distal piece is bidentate; the special tooth is rather slender and is moderately CTirved forwards; the subapical tooth is of moderate size, projects at right angles to the axis and is farther distad than in makemoana; the piece gradually widens proximad to the usual protuberance but does not have a distinct subbasal tooth, from the protuberance narrowing to the point of attachment as usual. (Plate 56, fig. 4). The pectinate setae have stalks of moderate length; the distal end is gradually clavately widened, the terminal piece being decidedly longer and relatively narrower than in makemoana and with the processes more even, the setae also being smaller. (Plate 56, fig. 3). Maxillae II with eight teeth on the right piece. Maxillae III of the right side is a strongly curved plate bearing ten teeth ; this is paired \vith two plates on the left side, the inner, more caudal, longer one of which has nine teeth, the other eight. The stems of the mandibles are short, narrowed caudad as usual, and well united anteriorly much as in the preceding form. The masti- catory plates are white; they he obliquely, their anterior margins making a reentrant angle of nearly forty-five degrees ; the anterior margin of each has two incisions dividing it into three rounded elevations or teeth ; there is also a weak indentation at the lower part of the outer end; the surface is striate. The blade of maxillae are of the usual general form, appearing a little more abruptly curved distally than in makemoana. The form of the carrier-plate could not be made out clearly; but it seems to be narrower across the caudal end than in make- moana, the form of which it approaches. Locality. Paumotu Islands: Makemo. One specimen from the coral at the bottom of the lagoon, depth 13 fms., 19 October, 1899. This specimen represents a form undoubtedly close to makemoana. The fact that the collection embraces only a single specimen of one species and an imperfect one of the other, makes it very difficult to judge the extent of varia- tion in characters and the precise relationship between the two. In the presence of various important differences, however, the two forms must be held as dis- tinct. The most obvious difference is presented by the branchiae. In the present form these extend both farther forward and farther caudad, and in particular an anterior group and a smaller posterior group are branched, pos- sessing two and three filaments instead of all being strictly simple. The peri- 248 THE ANNELIDA POLYCHAETA. stomium is longer relatively to the succeeding somites. The tentacular cirri are distinctly longer, reaching the middle of the prostomium instead of only near the middle of the peristomium, and they are more distinctly annulate. The tentacles are decidedly longer and consist of more articles, the inner paired ones, e. g., reaching the ninth somite instead of only the fourth and consisting of twenty articles instead of fourteen. The pectinate setae are much smaller and have the clavate apical piece relatively decidedly longer and narrower. In the compound setae the apical piece has the subapical tooth farther distad and relatively larger; and the setae as a whole are much coarser. The crochets are very close in size and structure. The mandible has its anterior margin distinctly dentate instead of essentially smooth, and the united pieces are pro- portionately broader. Leodice oliga papeetensis, subsp. nov. Plate 55, fig. 8-10; Plate 56, fig. 1. This form is represented only by the anterior portion of one specimen. This fragment, consisting of thirty-seven somites, is about 8.5 mm. long, with a maximum width o,f 2 mm. The general color is dark yellow without distinct markings. The tentacles, parapodia, cirri, and branchiae are paler, whitish. The tentacles are slender and strongly annulate as in oliga, the articles similarly short and submonihform. The median reaches somite XI and con- sists of twenty articles; it may have lost some terminal articles. The inner paired tentacle reaches somite V on one side and consists of fourteen articles; on the other reaches somite XI and consists of eighteen somites, the tip of the first evidently having been broken off. The tentacular cirri are very slender and at present do not extend beyond the anterior margin of the peristomium. The branchiae begin on somite VII, as in the typical form, as a simple fila- ment, but unlike the condition in the type-form, this filament is very much shorter than the cirrus. (Plate 55, fig. 8). The second branchiae consists also each of a single filament which is very slender and much shorter than its cirrus, although clearly exceeding the first in length. The fourth and succeeding branchiae, to and including the fourteenth, consist each of two filaments which seem in all cases to be exceeded by the notocirri. (Plate 55, fig. 9) . The branchiae from the fifteenth are again simple and decrease in size caudad so much as to be LEODICE OLIGA PAPEETENSIS. 249 practically if not quite obliterated on the last parapodia of the fragment. (Plate 55, fig. 10). Whether they appear again and increase in size farther caudad can only be conjectured. The pectinate setae are very similar in general structure to those of oliga; but the end-portion is larger and widens more strongly, though not so abruptly as in makemoana. The compound setae are so far as can be detected, identical in structure and size w-ith those of the species. The dorsal setae are capillary and di'awn out to a very fine tip as in oliga. The right maxillae II have seven stout teeth, the left six. The right plate of maxillae III have ten teeth and is paired with two plates on the left side, of which the inner has eight teeth and the outer one seven smaller teeth. The anterior border of the mandibles presents two rounded excisions as in the spe- cies. Locality. ^Society Islands: Papeete. One incomplete specimen taken on the shore, 9 November, 1899. The most obvious difference from the species is in the branchiae, which are throughout shorter than the notocirri instead of greatly exceeding them in the widest region of the body. They also seem to become obUterated toward the middle of the body, whereas in oliga they remain well deA-eloped tlu-oughout. The branched branchiae begin with the fourth and end with the fourteenth, instead of beginning with the second and ending with the eighteenth, and these seem to be uniformly bifilamentous instead of in considerable part trifilamentous. The pectinate setae differ in form as above described. The teeth of maxillae II and III differ in number. The constancy of these differences cannot be correctly estimated until more abundant material of the two forms has been studied. Leodice pauroneurata, sp. nov.^ Plate 57, fig. 8, 9; Plate 58, fig. 1-9; Plate 59, fig. 1-3. Dorsum brown, of a weak reddish tinge anteriorlj% a paler band along each side above parapodia; venter brown, paler along lateral portions, the parapodia and adjacent lateral region being similarly light. Tentacles and cu-ri light yellowish. Setae hght yellow. Total number of somites present in type, ninety-seven. Total length, 42 mm. Greatest width, exclusive of parapodia, 5 mm. Prostomium deeply retracted into the peristomium, the bases of the tenta- ' iraOpjs, small, few, and vApov, filament. 250 THE ANNELIDA POLYCHAETA. cles being in contact with or embraced by the latter. The prostomium is deeply divided by a median incision into two lobes, the furrow continuing distinctly to the base of the median furrow ; each lobe is oblique and is divided by a weak furrow into a larger inner and a smaller outer division. The tentacles are arranged in a semicircle in contact with the peristomium. The median tentacle has the apical portion broken off ; as it is, it reaches somite VI ; it is smooth, without annulations or wrinkles. The inner paired tentacles reach somite VII; they are a Uttle more slender than the median and are strongly tapered; each has a wholly smooth proximal division embracing more than two thirds the total length, followed by three short joints, of which the first is more vaguely separated, the other two distinctly so. The outer paired tentacles, more slender than the inner ones, are very short, reaching only to somite II; each ends in two or three short articles, the longer proximal division being wholly smooth. (Plate 58, fig. 5). The first somite, or peristomium, is dorsally about equal to the succeeding two and a half somites. Dorsally the anterior margin is smooth and evenly incurved and the dorsal surface is smooth. Laterally, where meeting the outer end of the prostomial lobes, there is a pronounced incision and furrow. The lower lip has its margin evenly incurved ; its surface is wholly smooth excepting for two sulci which cross it longitudinally, one each side of the middle. The second somite is distinctly set off above between the cirri and ventrally, but, as usual, is wholly fused with the first laterally. Above, it is shorter than the third somite. Cirri are short and slender subulate appendages which do not quite reach the anterior margin of the peristomium. Proximally each cirrus is smooth, while distally, over more than half the length, it is annulate, the annuli being short and only moderately distinct. (Plate 58, fig. 6). The third and succeeding somites bear parapodia. They are regular and undivided excepting that the more anterior ones are each crossed above by a weak furrow separating off a much shorter anterior division. In the widest part of the body (near somite XII), the somites are about ten times as wide as long. Somites are strongly arched and are nearly smooth; from the seventh caudad they have a sharply impressed median longitudinal furrow. Ventrally the somites are but sUghtly convex; they are crossed longitudinally by a pronounced neural furrow. From the region of the twelfth somite the body narrows strongly cephalad and more gradually but decidedly caudad. The pygidimn in the type appears to have been broken off so that its character and that of the anal cirri cannot be given. LEODICE PAURONEURATA. 251 The parapodia are short and bluntly rounded. The dorsal cirri are acumi- nate distad as usual. They are wholly smooth, showing no trace of annulations. They are longest in the anterior region, where, however, they are relatively but moderate, caudad becoming shorter and more slender. The ventral cirri in the anterior region consist of a stout, cylindrical, proximal, division and an abruptly narrower and very short, rounded, largely noduliform article. In the posterior region they are much smaller, taking on first a more slenderly cyhndrical form with no distinct distal article, and then becoming reduced to a mere nodule. Branchiae begin on the tenth somite and are present on all excepting the last three or four somites. The first branchia consists of two equal filaments springing from a short, thick, common base. (Plate 58, fig. 7). The second has two filaments, of which one is bifid. The third has also two filaments of greater length. (Plate 58, fig. 8). The fourth has three filaments, of which the median is longer than the laterals. The fifth has four filaments springing from a more elongate common stalk. The sixth and seventh have again three -filaments, the eighth two, and the ninth, tenth, eleventh, and twelfth, three. (Plate 58, fig. 9). The thirteenth has four filaments, of which one is bifid at the tip and one bears a short lateral bud below its middle. (Plate 59, fig. 1) . The fourteenth branchia has two filaments, the fifteenth, sixteenth, and seventeenth three, and the eighteenth again but two, the nineteenth and twenty first three (the twenty second missing), the twenty third to thirty first two, the thirty second one, the thirty third two, the thirty fourth one, the thh-ty fifth to thirty ninth two, the fortieth one, the forty first and forty second two, the forty third one, the forty fourth to forty seventh two, the forty eighth three, the forty ninth two and the fiftieth again three. From this region (fiftieth to sixtieth somites) caudad the branchiae show a decrease in length which in the last branchiferous somites is pronounced; most of them consist of three filaments, some of four. (Plate 59, fig. 2). Thus the number of filaments varies irregularly from one to four, one being least common, two and three the most conunon, the latter nmnber predominating in the caudal region. The brancliiae are always shorter than the cirri. Acicula black, stout, distally acutely aciuninate and a Uttle cm'ved, the tips freely projecting. Often transversely rugose below tip and sometimes appearing to have a barb on one side. Anteriorly the acicula are two in number, but in the posterior region there are often three. Dorsal acicula represented as usual by a small fascicle of transparent fibers extending to base of dorsal 252 THE ANNELIDA POLYCHAETA. cirrus; in some cases in the posterior region the fibers are brownish. Setae of the usual four kinds. The dorsal setae are fine, cylintkical, and acutely pointed, strictly capillary and not at all limbate. Among these are the delicate, trans- parent, pectinate setae which are more numerous than usual. These have exceptionally long stalks. The appendages are rather narrowly cuneate; the teeth are extended into filaments which often curl toward the middle of the series and in some increase progressively in length from one end of the series to the other. (Plate 57, fig. 8). The compound setae, composing the conspicuous ventral fascicle, are much coarser than the other ones. Each presents a decidedly curved shaft which is conspicuously clavately widened distad. The shaft at its wider distal portion is strongly obhquely striate as usual. The distal divi- sion, or appendage, of the compound setae widens a little above the narrowed basal portion by which attached, and then narrows gradually distad; presenting a moderate subbasal angle but with no distinct tooth at that level; at the distal end is a suberect, moderately curved, terminal tooth or hook, below which is the larger subapical tooth projecting at right angles to the axis of the appendage. The edge of the transparent membranous guards is proximally straight or slightly incurved and finely, closely serrulate, bulging out above the subapical tooth and extending distinctly over and above the apical tooth; obliquely striate. (Plate 57, fig. 9). The crochets begin in the parapodia of the twenty ninth somite. These are stout, black, aciculiform setae extending obliquely across acicula proper in an ectoventral direction, with the tip emerging near the base of the ventral cirrus. Each as a whole is strongly curved, with the concavity ectad, the apical portion becoming straight or slightly curved in the opposite direction; at the tip are two bluntly rounded teeth covered, as usual, by the membranous guards. (Plate 58, fig. 1). Maxillae light brown, black edged, not heavy. Maxillae I with plate formed by fused carriers, acutely notched behind, convex on each side, moder- ately narrowed distad, and then again widening; narrowly acutely incised along middle Une anteriorly with a narrow furrow connecting anterior and posterior incisions; each half of plate concavely depressed. Each blade has the ordinary falcate form, moderately narrowed distad, with the tip bluntly rounded, upper surface nearly flat, or somewhat concavely depressed from side to side, the margins being more or less elevated. (Plate 58, fig. 3). Maxillae II with outer edge proximally elevated but not reflexed, or at most only very nar- rowly so; on right side with seven teeth, on left with six, decreasing in size proximad, the last being very small, all in type apically rounded; proximad of LEODICE NESIOTES. 253 teeth a smooth, straight edge about equal in length to the dentigerous portion. (Plate 58, fig. 4). Maxillae III with margin crenate, the teeth being small and marginally rounded; left plate with eight teeth, right with ten. The unpaired plate not detected. Mandibles with masticatory plates large and white. Each is obliquely subovate, with the outer end rather narrow; anterior edge not at all dentate and outer end not incised. Stems of mandibles blackish; nearly straight, being but slightly cui-ved caudally; conspicuously narrowed caudad, the caudal ends narrow and subacutely pointed. (Plate 58, fig. 2). Locality. Off Galapagos Islands: Sta. 3401 (lat. 0° 59' S., long. 88° 58' 30" W.). Depth 395 fms. Bottom, Globigerina ooze. Bottom temp. 43.8° F. 28 March, 1891. One specimen containing eggs in posterior segments. While this species is Uke L. contingens, L. nesiotes and others of the same group in bearing branchiae continuously to or nearly to the caudal end of the body, it differs from them in having the branchiae rather arbuscular than pin- nate and in the much reduced number of the filaments. The species has points of resemblance to the wide-spread L. vittata (Delle Chiaji). In the latter species, however, the branchiae begin much farther forward (somite V). The branchiae also are much larger than the much reduced ones of the present species and the filaments are more pinnate in arrangement. Its crochets differ in structure, as do the compound setae in some details. The first maxillae differ conspicuously in form, having the carriers strongly narrowed caudad, subtriangular, instead of being expanded semicircular ly in this region. Leodice nesiotes, sp. nov.^ Plate 57, fig. 6, 7. Color brown of dilute chestnut cast, darkest along middorsal line. Tenta- cles, parapodia, cirri, and branchiae paler, more yellowish. The caudal end of the type is missing, so that the total number of somites is uncertain. There are in the incomplete specimen one hundred and one somites. The length is 90 mm., and the greatest width, exclusive of the parapodia, is 5 mm. Prostomium short, narrower than the peristomium; deeply vertically incised in the median line in front; each half very obUque, conspicuously wrinkled; the anterior surface deeply depressed so as to leave a higher dorsal wrinkle and a ventral marginal ridge. Tentacles of tvpe rather irregularly ' vqaiuiT-r)';, islander. 254 THE ANNELIDA POLYCHAETA. annulate, though the transverse wrinkles may to some extent be due to partial drying. The median tentacle reaching to somite IX ; the inner paired tentacles somewhat more slender than the median, but likewise reaching the ninth somite. The outer paired tentacles are very short, reaching only to the second somite, though the tips may have been broken off. Peristomium in length equalling or exceeding the succeeding three somites. Indented at the median line in front, the anterior edge extending farther forward laterally and ventrally. Dorsally conspicuously ribbed longitudinally. Ven- trally transversely wrinkled and the lower lip crossed by longitudinal sulci. Lower Up mesaUy deeply incurved. Somite II apodous as usual. Distinct dorsally and ventrally, but laterally completely fused with somite I. Dorsally longitudinally ribbed. Cirri slender, weakly annulate, extending but slightly beyond anterior margin of peristomium. The succeeding somites bearing parapodia. Regular and undivided. Dorsally strongly convex; with a sharply impressed median longitudinal furrow, this less distinct anteriorly ; longitudinally costate, the impressions distinct laterally, fading out toward the middorsal region, and becoming less distinct, or absent in caudal region. Ventrally only weakly convex; with a deep median longi- tudinal neural furrow. Body becoming widest at or near the twenty sixth somite. In this region the somites are five times wider than long. From this point the body narrows strongly cephalad and is narrowest at the third somite; caudad it remains of nearly uniform width to the caudal region, where it narrows very gradually. Parapodia of the usual short and simple type. Neurocirri in anterior region with conspicuously swollen bases, ovate in outline, and short, subconical, apical divisions; caudad they undergo the usual change, the basal division becoming smaller and not abruptly separated from the tip. Notocirri long, much exceeding the neurocirri; thick proximally, but subulate and slender distally. The branchiae begin on the ninth somite and continue throughout most or all of the length (the caudal end of the type is missing and the presence of branchiae on the somites of that part is uncertain, though probable) . They are throughout unilaterally pectinate; they are moderately long, moderately exceeding the cirri, and, when laid against the dorsum nearly reach to the mid- dorsal line; they are not erect, the flattened stalk being rather weak and show- ing a tendency to curl; filaments simple, unusually short and relatively wide, flattened and often ciu-ling. The maximum number of filaments noted in the LEODICE NESIOTES. 255 type is fourteen. The number seems to remain high (near twelve) throughout most of the length. A bundle of fine, fiber-like, pale acicula extending into base of notocirrus. Principal acicula black, stout, distally acutely pointed, gently doubly curved distad; the tips projecting freely among the bases of the dorsal setae; two in number in each parapodium. Setae of four kinds. The dorsal capillary setae compose a rather small fascicle. The setae are transparent, fine, and narrowly wdnged. Among these are the fine, transparent pectinate setae. Each of these has the usual delicate stalk bearing the cuneate or subcampanulate head, the free edge of which is finely pectinate, each tooth extending into a slender, curving filament of considerable length. The compound ventral setae are coarse and are yellow in color. The shaft of each is curved, with the concavity ventrad, and is strongly clavately widened distad. The appendage, or blade, is short and is tri- dentate, there being a distinct subbasal tooth in addition to the two distal ones. The apical tooth is subvertical and gently curved; the subapical tooth is large, subcorneal, and its axis makes a considerable angle with a line at right angles to the axis of the blade ; the subbasal tooth has its upper line nearly horizontal ; the membranous guard bulges a little between the subbasal and subapical teeth and extends over the apical tooth, ending a Uttle above the level of the tip of the latter in a low point; edge of guard apparently smooth. (Plate 57, fig. 7). The crochets, occurring in the parapodia of the middle and posterior regions are stout and black in color. Each, as usual, extends obhquely across the acicula, its distal end lying near the base of the neurocirrus. The mandibles have the masticatory plates large, oblique, subelliptic and white, each notched at the exterior end but with the anteromesal edge wholly smooth; stems black, stout, attenuated caudad, weakly united anteriorly. (Plate 57, fig. 6). Maxillae II heavy, black, the left with five stout teeth addi- tional to the angle at anterior end of proximal smooth edge, the right with six. Maxillae III on left side with six t^eth additional to a reduced one at angle of the smooth proximal edge; right plate with ten teeth. The unpaired left plate with four teeth. Locality. Marshall Islands. Depth, 12 fms. Expedition of 1899-1900. A female specimen containing eggs came up on the anchor of the Albatross. In the character and arrangement of its branchiae this species belongs in the same group as L. contingens. From that species and from L. hilobata it is at once distinguishable by its much longer branchiae and the shorter, less crowded, filaments of the latter. In general structure it resembles hilobata; but the 256 THE ANNELIDA POLYCHAETA. incomplete description of the latter, due to imperfection of the type, makes a wholly satisfactory conclusion as to their relationship difficult to draw. An important difference appears to be in the tentacles, which are whoUy smooth in bilobata, but are jointed in nesiotes. L. muUipectinata differs in its shorter tentacles, with the median and inner paired ones distinctly unequal, in lacking a distinct subbasal tooth on the blade of the compound setae, etc. L. antennata, so wide-spread in the Indo-Pacific region, and the Japanese L. microprion differ, among other features, in having the branchiae begin farther forward. The Philippine L. flavofasciata also differs in having the branchiae begin on somite VII, in having the tentacles wholly smooth, etc. The Pacific Ocean species having pectinate branchiae throughout the length of the body may be separated by the following: Key. a. Branchiae beginning on somite IX. 6. All branchiae distinctly shorter than the dorsal cirri L. contingens, sp. nov. 66. At least the more posterior branchiae considerably longer than the dorsal cirri. c. Tentacles unjointed, wholly smooth L. bilobata (Treadwcll). cc. Tentacles jointed. d. Inner paired tentacles much shorter than the median, the latter reaching to somite VII; appendage of compound setae with no distinct submedian tooth. L. mullibranchiala (Moore). dd. Inner paired tentacles equalling the median in length and reaching to somite IX; append- age of compound setae with a conspicuous submedian tooth L. nesiotes, sp. nov. aa. Branchiae beginning cephalad of somite IX. 6. Tentacles wholly smooth. Body covered with interrupted yellow bands L. flavofasciata (Grube). 66. Tentacles annulated. c. Annulations strongly marked, and tentacles in part moniliform; the articles numerous and short; crochets tridentate L. antennata Sayigny. cc. Annulations of tentacles weak; crochets bidentate. d. Joints of tentacles long and few; first branchia with three filaments, on somite VI; right maxilla II with five teeth, right maxilla III with seven. . , .L. microprion (Marenzeller). dd. Joints of tentacles short and numerous; first branchia with but one filament, on somite VII; right maxilla II witli eight teeth; right maxilla III with ten teeth. L. panamena, sp. nov. Leodice panamena, sp. nov. Plate 59, fig. 4-8; Plate 60, fig. 1-5. The type is incomplete, the posterior region being lost. The anterior fragment, consisting of seventy-three somites, is 30 mm. long, with a maximimi width, exclusive of parapodia, of 4 mm. The body is widest at the caudal end of the fragment from where it narrows gradually cephalad, a Uttle more strongly narrowing at the anterior end. LEODICE PANAMENA. 257 The general color of the body is browii without markings. The tentacles, cirri, and branchiae are very dilute yellow. The prostomium is a Uttle more than half as long as the peristomium, than which it is considerably narrower. It is strongly bilobed, the median vertical incision being deep and acute. The lobes widen in subpyriform manner from above ventrad. On each a smaller dorsal lobe is vaguely separated from a much larger ventral one. The median and inner paired tentacles are arranged in a transverse row in contact with the edge of the peristomium, while each outer paired tentacle is distinctly farther forward and in front of the black eye-spot, which is partly covered by the border of the peristomium. The median tentacle has lost the tip and reaches only to the third somite. The inner pau-ed tentacles, which also may not be complete, reach to the same somite. The outer paired tentacles do not reach fully to the caudal edge of the peristomium. The tenta- cles are all annulate throughout their length, the articles all being short and relatively broad, with the constrictions between them not deep. The articles are more distinct distally than proximad. The ceratophores are short and not thick; from them the antennae widen to about the end of the first third and then narrow strongly distad. The peristomium is nearly of the same length as the next three somites together. It is smooth dorsally. The anterior margin above is nearly straight excepting for a shallow median excavation opposite the base of the median tentacle. On each side the anterior margin is slightly notched, and from the notch a short sulcus extends caudad. The lower lip is nearly smooth, except for a few weak transverse sulci. Its anterior margin is widely but not deeply incurved, and is smooth. The second somite, which is apodous, is fused with the peristomium laterally, but is distinctly set off dorsaUy and ventrally. The tentacular cu-ri are stout at base, strongly narrowing to a point distad ; they are short, scarcely extending beyond the anterior margin of the peristomium. AnnuU are only ver>^ vaguely indicated. The third and succeeding somites, which bear parapodia, are regular and wholly undivided. The third is longer than the second, the others increasing in length to the sixth inclusive, after which a number become shorter before the ordinary length is again resumed. At the widest part of the type, or near the seventieth somite, the somites are about nine times wider than long. Dorsally the somites are moderately convexly arched, the arch not being high. From the eighth somite caudad there is a median longitudinal depression, or furrow. 258 THE ANNELIDA POLYCHAETA. which is most distinct anteriorly. The venter is weakly convex. From the fourth somite caudad there is a distinct neural furrow of moderate width and depth. The parapodia are very small, subcylindrical and distally rounded processes. The notocirri are not jointed, though some of them may give the impression of a very vague, irregular annulation ; they are stout at base, from which they taper strongly to a point. They increase in length from the first to about the twelfth, where they extend near halfway to the middorsal line when laid back against the body. They become shorter and more slender caudad, the base or cerato- phore appearing there especially abruptly thicker. The nem'ocirri are short. The first four to six appear subcorneal with the base constricted and the terminal article continuing the outline of the proximal without abrupt change. The cirri then become stouter and cyUndrical, with the small terminal article abruptly very much narrower. They continue of this form to the end of the fragment. The branchiae begin on somite VII and occur on all subsequent somites to the end of the fragment. Excepting the first, they are of the unilaterally pectinate type. The filaments arise at an angle of about forty-five degrees to the stem, and the terminal filament is parallel with the others. The individual filaments are shorter than the notocirrus. Each of the first branchiae is a simple, unbranched, slender filament shorter than the notocirrus. (Plate 59, fig. 4). The second branchia on the left side has foiu- filaments, the right apparently but three. Of these four filaments the one next the last is longest, the first and last the shortest. (Plate 59, fig. 5). The third branchia is likewise composed of four filaments similarly related, but they are distinctly larger than in the second. The fourth has six filaments, the fifth seven, the sixth has six prunary filaments, but of these the second gives off two lateral branches of which the proximal one is much the longer, making the total number of filaments eight, the maximum number noted. (Plate 59, fig. 6). In the thirty eighth and for- tieth branchiae the number of filaments has again fallen to five. The forty second branchia has four filaments, the number that prevails on succeeding branchiae to the seventy third somite, the last present in the type, though only three filaments occur in some. (Plate 59, fig. 8). The filaments are nearly always entirely simple, the branched condition being exceptional. The bran- chiae are erect, usually curUng away from the body rather than lying against it. When stretched back against the body the longer branchiae fail much of reaching the middorsal line. The acicula proper are pale in color. They are comparativelj^ slender and LEODICE PANAMENA. 259 each has distally a double curve, the more distal curve being the more pronounced. The tips project freely beyond the surface of the parapodium, as usual. The single crochet, as usual, extends within the parapodium obliquely across the acicula and setae to emerge at the base of the neurocuTus. It curves moderately ventrad, i.e., is convex ectodorsad. At the tip it is bidentate, presenting the ordinary, suberect, stout apical tooth and a very stout, somewhat conical, sub- apical tooth, which in outline has the upper edge convex, the lower concave. The membranous guards rise above the level of the apical tooth and narrow to a subacute angle at the tip. (Plate 60, fig. 1). The pectinate setae have the ordinary general structure. Each presents a dehcate stalk bearing distally an elongate, narrowly cuneate appendage, the distal edge of which is finely pectinate. At one end of the series of teeth is a more elongate process, or mucron, of moder- ate length. (Plate 60, fig. 3). The principal dorsal setae are capillary; they are non-limbate and distally reduced to a very fine tip which is usually moderately curved. The compound setae of the ventral group are much coarser than the capillary tj-pe. In these the shaft is long, gently cm-ved, and of nearly uniform diameter to near the distal end where it enlarges subclavately ; on the convex side, toward the distal end, the border is crossed by fine, obhque sulci giving the edge a weakly serrate appearance. The distal piece is distally bidentate, presenting an erect apical tooth and a basally broad, low, conical subapical tooth. The subbasal prominence is low and rounded with, in outUne, a short horizontal upper edge, so that it often appears like a blunt tooth. The mem- branous guards rise considerably above the level of the tip of the apical tooth and narrow to a point distally. (Plate 60, fig. 2). The maxillae are blackish in color and are well chitinized. The mandibles are also blackish excepting the masticatory plates, which are white. The mandibles are relatively narrow across the anterior end. The masticatory plates relatively short from side to side. Their projected anterior edges meet at a very obtuse angle, but little less than one hundred and eighty degi'ees. The edges are straight and are but finely and very weakly wavy, presenting no distinct teeth or excisions. Each plate at its outer end has the usual slight indentation. The stems are nearly straight. They are broad, narrowing from the middle caudad and diverging from each other. (Plate 60, fig. 4). Maxillae I have the piece formed by the united carriers \'ery elongate. It is narrowest anteriorly, the nearly straight sides diverging moderately caudad and rounding in about the ectocaudal corners, the caudal end convex. The carrier has its upper surface somewhat concave. The blades are broad, especially proximally, and are 260 THE ANNELIDA POLYCHAETA. distally rather abruptly incurved and falciform. Maxillae II have the ecto- caudal corners elevated as usual, but the elevated portion is short and rolled in only a short distance. The right maxiUa has eight somewhat recurved teeth, of which the one at each end is reduced. The left has but five similar teeth. The right maxilla III is a strongly curved plate bearing along its free edge the teeth. It is paired with two plates on the left side, of which the more anterior has but six similar teeth and the more posterior, lying close along maxilla II, has seven larger teeth comparable to those of maxilla II. Maxilla IV has a single tooth. Locality. Near Panama. Shore. Exped. 1891. One specimen. This species is at once separated from the widespread L. antennata Savigny, which it in many ways resembles, and its near relatives in having the crochets bidentate instead of tridentate. Aside from important differences in setae, maxillae, etc., it differs from L. multibranchiata (Moore) and L. nesiotes, sp. nov., in having branchiae begin on somite VII instead of on IX, and also the first branchia is composed of but a single filament instead of seven or more. In the character of the branchiae and notocirri the species is very similar to L. microprion (Marenzeller). It is like that species in the prevalence of four filaments to the branchiae, in having the maximum number of filaments eight, and in the general order in which reduction takes place. It differs in having but one filament in branchia I instead of three and in having this on somite VII instead of VI. It also differs conspicuously in the form of the carrier- plate of maxillae I, which is relatively much longer and the sides of which are nearly straight instead of being strongly incurved; the blades are much more strongly curved as judged from Marenzeller's figiu-e (Denskchr. K. akad. wis- sensch. Math. nat. klasse, 1879, 41, p. 135, pi. 5, fig. Ic). Maxilla II of the right side has eight teeth instead of five and the left side five in place of six, the contrast between the sides being thus much more pronounced. The unpaired left plate has seven teeth instead of but foiu", and the right maxilla III ten instead of but seven, the left six instead of four. See also p. 256. Leodice contingens, sp. nov.^ Plate 57, fig. 1-5. The type is brown throughout, the color being nearly uniform and present- ing no distinct markings. ' contingere, to border, touch. LEODICE CONTINGENS. 2(il The number of somites in the type is one hundred and twenty-two, of which the last thii-teen are apparent!}^ regenerated. The total length, exclusive of the anal cirri and the tentacles, is nearly 116 mm. Greatest width, exclusive of parapodia, 6 mm., to tips of setae, about 9.2 mm. Prostomium broad, protruding laterad on each side; deeply sunken into peristomiiun , the exposed portion short. Anteriorly deeply vertically incised, leaving a thick palpus on each side. Palpi strongly diverging from above ventrolaterad ; each slightly indented, presenting a smaller border above the indentation and a larger thicker one below it. Tentacles arranged transversely in a semicircle, the laterals on each side rather closer together than to the median, the outer lateral inserted much farther forward than the inner. Tentacles mostly smooth, or but vaguely wrinkled distally; each with a very short but distinctly separated ceratophore; tips slender. Median tentacle reaching to somite VIII; inner paired tentacles reach to somite VI; outer paired tentacles much shorter, reaching only to the edge of somite III. Peristomium in length equalling the next three somites. Anterior border indented on each side; below the indentation is the thickened lower lip, the margin of which is concave and is crossed longitudinally by sulci, appearing crenulate. Somite II apodous. Fused laterally with somite I, but again distinct ven- trally. Cirri more slender than tentacles, long and subulate, reaching forward to anterior third of exposed portion of prostomium; weakly wrinkled or annulate, more distinctly so distaUy. Somites from III caudad bearing parapodia. All regular and undivided. In widest part of body near six times wider than long, while in the posterior region the width may be less than tliree and a half times the length. Somites strongly arched above; smooth; ventrally nearly flat, with the median neural furrow distinct but not deep. The body attains its greatest width near somite XI or XII. It decreases in width very gradually caudad to the posterior end, where it narrows more abruptly to a point. Pygi- dium subtnuicate; below the anus arise two smooth, subulate cirri 6 mm. long. Parapodia of the usual simple form, moderate in length. Neurocirri in the anterior region with conspicuously thickened bases which in ventral view are oblong in outline; the more slender tip is a short, bluntly conical process; posteriorly the bases become less swollen and the apical portion more cylindrical. Notocirri notably long, being in the anterior region four or five times as long as the parapodium; smooth, tapering to a point distad. In the posterior region the notocirri are more slender and are relatively longer. 262 THE ANNELIDA POLYCHAETA. The branchiae begin on somite IX and occxir on succeeding somites to the end of the body, excepting on the last two or three. They are short and incon- spicuous, being exceeded in all cases by the cirri ; erect and mostly free from the dorsum. They are throughout unilaterally pectinate, the stem arising from base of notocirrus and slenderly tapered. Filaments arising nearly at right angles to the stem, close and often crowded, parallel, slender, two thirds or less the length of the cirrus. They are simple but often branch a little above origin into two filaments which are usually equal but may be unequal in length. The first branchiae have four or five filaments, the second about eight, the fifteenth, sixteen or seventeen, counting the terminal extension of the stem, of which two are divided near their origins, making the total number of filaments eighteen or nineteen, and the thirty second branchiae have again but eight or ten filaments. (Plate 57, fig. 2). The acicula are black and opaque. In the anterior parapodia there are two acicula with their tips, which are paler, projecting among the bases of the dorsal setae and two or three much finer and closely appressed acicula extending into the base of the notocirrus. Farther caudad the dorsal acicula become reduced to a small and inconspicuous fascicle of fibers. The two ventral aci- cula are stout and black throughout, with their tips projecting farther than in the anterior parapodia; the tips are acutely pointed, and are either straight or very weakly curved. The setae are comparatively long, all clearly exceeding the neurocirrus, though much shorter than the notocirrus. Those of the dorsal fascicle are much longer than the ventral ones. In the dorsal fascicle the princi- pal setae are about twelve in number. They are distinctly margined or winged along two sides; the distal end is narrowed to an acute point and is curved; they are obliquely striate, though the striae are not always pronounced. (Plate 57, fig. 3). Among the limbate setae are the much shorter pectinate ones. These have the usual slender stalks bearing the cuneately widening distal bodies which are finely pectinate along the distal margin; the marginal process, or mucron, borne at one edge is fine and short, or but moderate in length. The less numerous setae of the ventral fascicle are compound. Their shafts are moderately curved and are strongly clavately widened distad; the appendages are short and distally bidentate, the upper tooth in the form of a hook, the infe- rior one much larger and projecting at right angles to the axis of the process; process widening proximad, with no distinct basal tooth; the usual delicate guard, which, but slightly or not at all, extends beyond the tip of the process; its edge veiy finely denticulate. (Plate 57, fig. 5). In each parapodium of the ONUPHIDIDAE. 2G3 middle and posterior regions there is a largely black aciculiforni seta, the crochet, running obliquely and projecting at the base of the neurocirrus. It is narrowed and curved at the tip, where it ends in a low, usually blunt tooth, below which is a much larger one. (Plate 57, fig. 4). Jaws rather heavy, hard, and black. Maxillae I with carriers firmly united into a rounded, laterally bulging, suborbicular plate; the blade just above base on ectal side with a projecting angle or tooth, above which it is of the ordinary falcate form; the blades have but little free motion, being closely united proximally and clasped by large reflex processes from the second maxillae. Maxillae II heavy; teeth six, stout, or seven, including a small, imperfectly separated, proximal one. Both plates alike, the teeth largest distad, preceded proximad by a long smooth edge. (Plate 57, fig. 1). MaxiUae III of left side with one plate bearing four small teeth, the other seven; plate of right side longer and bearing nine teeth. Locality. Galapagos Islands : near Hood Island, Ripple Point. Sta. 4642 (lat. 1°, 30' 5" S., long. 89° 35' W.). Depth 300 fms. Bottom temp. 48.6 F. Bottom of broken shells and Globigerina. 7 November, 1904. One female turgid with eggs. In having pectinate gills over the entire length of the body this species is like the following reported from the Pacific Ocean: L. antennata (Savigny), L. microprion (Marenzeller), L. flavofasciata, (Giube) L. bilobata (Treadwell), and L. iHultipectinata (Moore). From L. muUipectinata, known from off the southern CaHfornian coast, the species differs, among other points, in having the dorsal setae strongly winged instead of being wingless, in having the blade of the compound setae differently formed, the maximum number of gill-filaments larger, the tentacles not distinctly annulate, the anal cirri but a single pair and these strongly tapered. From L. bilobata, an Hawaiian Island form, the species differs in having the paired tentacles relatively decidedly shorter, in the different structure of the compound setae, etc. The present species in general structure seems to approach L. microprion rather closely; but it differs, for example, in having the branchiae begin on IX instead of on VI and in having a much larger maximum number of gill-filaments (seventeen or nineteen instead of but eight) and in the larger number of teeth on the paired plates of maxillae III. Onxjphididae. As in the Leodicidae, to which the present family is very close and with which, consequently, it is often united, the body is elongate and vermiform, 264 THE ANNELIDA POLYCHAETA. composed of numerous simple somites, and with a smooth and iridescent skin. The prostomium differs from that of the Leodicidae in bearing ahvays two frontal tentacles in addition to five posterior ones, the total being uniformly seven. Palpi present. Eyes two, or none. The peristomium differs from that of the preceding family in being uni- formly entu-e, with no trace of biannulation. Tentacular nuchal cirri may be present as a single pair, or absent. Branchiae either present or absent, when present either simple filaments or variously branched. Parapodia and setae in general as in the Leodicidae, as are the other more important structural characters. Unlike the Leodicidae, almost all members of this family occur at consider- able and great depths, a number of species, such as Leptoecia ahyssorujn (p. 320), occurring below the two thousand fathom line. The tubes are sometimes composed exclusively of the hardened secretion from the animal, as is the case with the remarkable, tough, horny and hyaline, quill-like tubes of Hyalinoecia giving the name to that genus. In other cases the secretion forms but a com- paratively thin fining membrane strengthened with a wall composed of various foreign objects, such as the long fibers, or spicules, of vitreous sponges, as in the case of Onuphis sombreriana Mcintosh, the shells of various Foraminifera and similar forms, as in the case of Paronuphis solenotedon (p. 310), or simply of fine mud, as in 0. proalopus, sp. nov., and 0. cobra, sp. nov. Key to Genera. a. Branchiae present. 6. With tentacular cirri. c. The frontal tentacles long and slender like the others Heptaceras Ehlers. cc. Frontal tentacles short, stumpy. d. With especially long simple setae in first three pairs of parapodia . . Rhamphobrachium Ehlers. dd. Without long simple setae on first three setigerous somites. e. Brancliiae simply cirriform or pectinate; eyes small, point-like, between median and posterior paired tentacles on each side Onuphis Audouin and Milne Edwards. /. First two pairs of parapodia not prolonged. //. First two pairs of parapodia prolonged, extending forward beneath the prostomium. Paranorthia Moore. ee. Branchiae in the form of a brush or plume, the filaments spirally arranged, the largest ones at the anterior end of the series; eyes large, between unpaired tentacle and median lateral on each side Diopatra Audouin and MUne Edwards. 66. No tentacular cirri; branchiae cirriform Hyalinoecia Malmgren. aa. With no branchiae. 6. With tentacular cirri, c. Eyes large, each between unpaired tentacle and median lateral one of corresponding side. Paradiopatra Ehlers. CO. Eyes small, punctiform, each situated laterally between the median and posterior lateral tentacle Paronuphis Ehlers. 66. With no tentacular cirri Leptoecia, gen. nov ONUPHIS PROALOPUS. 265 Onuphis Audouin and Milne Edwards. Hist. nat. litt. France. Ann61ides, 1834, 2, p. 151; Qu.4.tbef.\ges, Hist. nat. anneles, 1865, 1, p. 350; Ehlers, Borstenwurmer, 1868, p. 296; McInto.sh, British annelids, 1910, 2, pt. 2, p. 404. Northia Johnston, Cat. annelids Brit, mus., 1865, p. 136. Nothria Malmoren, Annulata Polycliaeta, 1867, p. 66. Tradopia Baird, Journ. Linn. see. London. ZooL, 1869, 10, p. 355. The species of Onuphis described below may be separated by means of the following : Ketj. a. Branchiae all simple. 6. Branchiae beginning on the si.xth parapodia; median tentacles shorter than the posterior paired ones O. lepta, sp. nov. 66. Branchiae beginning on the fourteenth parapodia; median tentacle longer than the posterior paired ones. c. Crochets of first parapodia composite; most branchiae as long as or longer than the noto- cirrus, wliioh in no case reaches halfway to the middorsal line; carrier of maxillae I broad caudally O. crassiseiosa, sp. nov. cc. Crochets of first parapodia simple; all branchiae decidedly shorter than the notocirri which are long, some almost reaching middorsal Une; carrier of maxillae I pointed behind, triangu- lar 0. cobra, sp. nov. aa. Brancliiae, at least in part, branched. 6. Anterior hooded crochets tridentate. c. Branchiae beginning on the sixth parapodia; first parapodia e.xtending directly forward well beyond middle of prostomiimi O. proalopus, sp. nov. cc. Branchiae beginning on the fifth parapodia; first parapodia oblique, not passing middle of prostomium 0. nannognaihus, sp. nov. 66. Anterior crochets bidentate. c. Branchiae beginning on the seventh parapocUa 0. litabranchia, sp. nov. cc. Branchiae beginning on the sixteenth or seventeenth parapodia. d. Branchiae beginning on the sixteenth parapodia; ceratophores of tentacles widest at middle, narrowed at both ends; end piece of pectinate setae short and broad. 0. pachybnenia, sp. nov. dd. Branchiae beginning on the seventeenth parapodia; ceratophores strictly cylindrical; distal division of pectinate setae verj' long and narrow O. socia, sp. nov. Onuphis proalopus, sp. nov.'^ Plate 40, fig. 3-8; Plate 41, fig. 1-10. The general color is brown, paler on each side in a stripe adjacent to the parapodia, these with their cirri and branchiae being yellowish. In the anterior region there is a somewhat obscure middorsal and midventral longitudinal whitish stripe. The tentacles are yellow. The type lacks the posterior portion. The fragment present is 65 mm. long with a maximum \vidth, exclusive of parapodia, of 2 mm. It consists of one hundred and eighty-two somites. ' TTpooXijs, springing forwards, and Trois, foot. 266 THE ANNELIDA POLYCHAETA. The prostoniium is wide in proportion to its depth, in anterior view being transversely elliptic in outline. It is comparatively long, being dorsally twice as long as the peristoinium. The surface in general is smooth ; there is a vertical sulcus on the anterior face from between the frontal tentacles ventrad. The palpi are large and conspicuous, thick and subconical, distally rounded. They are contiguous mesally. Each extends outward beyond the side of the pro- stomium. The tentacles are arranged in a transverse ellipse. The frontal tentacles are separated by less than half their proximal diameter; they are sub- cylindric and distally rounded. The dorsal tentacles are each composed of a conspicuous, distinctly annulate and strictly cylindrical ceratophore and a long, smooth style which proximally is as thick as the ceratophore, but gradually tapers distad. The anterior paired tentacles reach to the fifth somite; the ceratophore consists of five very short articles and a distal smooth division clearly more than a third but less than half the total length; the style, stout at base, tapers to a fine point. Each posterior paired tentacle is inserted midway between the corresponding anterior tentacle and the median tentacle, and reaches to somite XVIII or XIX; the ceratophore is a little longer than that of the anterior paired tentacles and consists of six short articles proximally and a smooth distal division less than half of the total length; the style narrows very gradually and uniformly to an acute tip. The ceratophore of the median tenta- cle is shorter than that of the posterior laterals, being nearly equal to that of the anterior laterals; it is composed of five short proximal articles and the usual smooth distal division ; the style is of the same form and nearly of the same length as that of the posterior laterals. (Plate 40, fig. 3). The peristomium dorsally is very short, being in the middorsal line not more than half the length of the prostomium or of the length of the second somite. On each side it projects conspicuously forward to embrace the pro- stomium. The lower lip is abruptly elevated above the level of the lateral surface on each side and is sharply limited ; it is broad and but slightly narrower caudad than across the anterior end; the anterior margin is in the form of a very obtuse V with the apex, which is caudad, narrowly truncate and each arm at its extreme outer end curving a little more directly ectad; there is a sub- quadrate area outlined on the middle of the surface by weak furrows. (Plate 40, fig. 5). The tentacular cirri are long and slender, each reaching forward beyond the bases of the frontal tentacles. (Plate 40, fig. 3). The first few metastomial somites are rather strongly arched dorsally, the arch becoming wider and lower caudad. Ventrally the somites are moderately ONUPHIS PROALOPUS. . 2G7 convex tlu'oughout. Most somites, excepting the first few, are a little depressed along the middorsal line and also along the midventral line. Intersegmental furrows deep and distinct. The first and second metastomial somites are about equal in length, which is nearly the same as that of the prostomium, and are about three times as wide across the anterior end as long. The third metastomial somite is shorter in about the ratio eleven to thu'teen. It shows a distinct transverse sulcus, there being only a weak transverse depression on the first two. The succeeding somites do not show a distinct transverse sulcus. They gradu- ally decrease in length to the seventh, which is between five and six times wider than long and which is scarcely more than half as long as the first metastomial. The following somites maintain practically this same actual length thi-oughout most of the fragment, the most caudal ones, however, being shorter in about the ratio of five to seven. The first parapodia are cylindrical and very long, and extend almost di- rectly forward along the sides of the peristomium and prostomium beyond the middle of the latter and very nearly to its anterior end, the cirri projecting beyond the anterior end. The notocirrus is attached above, a little proximad of the middle, has a narrowed cirrophore, just above which it is moderately thickened, and then tapers to a point. The neurocirrus, attached on the ventral side, and nearly opposite to the notocirrus, is similar in form, but is smaller. There is only a slight presetal elevation, whereas there is a tapered, cirrus-like, postsetal process as long as the neurocirrus. (Plate 41, fig. 3). The succeeding five pairs of parapodia are smiilarly attached to the anterior border of their somites but project less directly cephalad and are shorter though still compara- tively long. (Plate 41, fig. 4). Beginning with the sixth, the parapodia, now- attached at middle of length of somite, extend more ectad, at the eighth directly so, at the same time becoming greatly shortened. (Plate 41, fig. 4). At the same time they are shifted dorsad and at the eleventh attain the dorsal level which is maintamed thereafter. Caudad the postsetal process gradually becomes shorter, appearing only as a short, thin lobe and finally quite absent caudad of the eight- eenth parapodia. The notocirri in the most anterior parapodia are long and slenderly tapering, reaching to or shghtly beyond the middorsal line. They continue to be prominent on all parapodia, but posteriorly they become ex- tremely slender and filamentous while maintaining the same or nearly the same length. The neurocirri are well-developed, tapering processes on the first seven pairs of parapodia. Beginning with the eighth parapodia they are reduced to flattened scutes merging in the glandular area. 268 THE ANNELIDA POLYCHAETA. Branchiae first appear on the sixth parapodia and continue to be strongly- developed on all subsequent parapodia to the end of the fragment (somite CLXXXII). The first and second branchiae are unifilamentous, each filament slender, tapered, and nearly equalling the notocirrus in length. The third to seventh branchiae, inclusive, are bifilamentous, the branch arising proximad of the middle and projecting forward at an angle of about forty-five degrees from the principal filament. (Plate 41, fig. 8). The eighth branchiae on the left side is trifilamentous, a second branch springing from the caudal side between the base and the first branch at a similar angle, while the right branchia is bifila- mentous. The ninth branchia on the left side, on the contrary, is bifilamentous, while that of the right side is trifilamentous. (Plate 41, fig. 9). Subsequent branchiae acquire four and then five or sometimes six filaments, these in the middle region of the body being, like the notocirri, long and surpassing the middorsal line, while their arrangement is prevailingly unilaterally pectinate. (Plate 41, fig. 10). Five filaments is the number maintained almost exclusively in the branchiae excepting in the most anterior ones and some irregularities in the most posterior, which are also shorter. The so-called dorsal acicula consist of a fascia of slender setae or fibers extending into the base of the notocirrus. The ventral acicula are arranged in a series, often of four. They are dark brown in color, and stout, distally finely pointed, the colorless tip projecting freely from the surface. (Plate 40, fig. 6). On each of the first five pairs of parapodia there occurs a series of stout compound crochets in which the joint is distinct. Each is distally tridentate, the apical tooth much larger, suberect, but curving distally outward beyond the others, which are short and project nearly at right angles to the axis. The membran- ous sheaths rise well above the apex, but are not prolonged into a slender tip. (Plate 41, fig. 7). In addition these anterior parapodia bear a small dorsal group of Umbate setae. These are short and very finely tipped, expanding near the middle of the exposed portion, where they are narrowly limbate, and again a little narrower proximad of this. On the sixth parapodia the compound crochets are replaced by stout simple setae, which are distally attenuated to a very fine tip. Farther caudad the true crochets make their appearance, these normally two, but sometimes three, in number in each parapodium. These are dark in color. The exposed portion of each is narrowed distad to a neck-like constriction below the teeth, which are two in number. The lower tooth is much the larger and is nearly transverse. The upper one, vertical proximally, is abruptly curved distally. The membranous guards scarcely exceed the teeth, ONUPHIS PROALOPUS. 269 and the distal edge is straight and runs obUquely from one tooth to the other. (Plate 40, fig. 8). The pectinate setae are transparent and delicate; the stalks are usually very long, variable in length; the expanded distal piece is large, in outUne somewhat cuneate but asymmetrical, one side being obUque and pro- longed, the edge of the other diverging but Uttle from the axial line; the distal edge is a httle oblique, its teeth nearly uniform in length. (Plate 41, fig. 2). The setae of the dorsal group are comparative^ short and slender; each is slenderly tapered to a fine tip, more or less bent near middle of exposed portion, and is narrowly limbate. The ordinary' ^'entral setae are coarse, a little bent or curved and drawn out distally to a fine point; they are narrowly bilimbate. (Plate 40, fig. 7). The maxillae are thin and translucent, kregularly blackish on part of the edges. Each carrier-plate of maxillae I is at the anterior end incurved, the remaining greater portion of the plate being semicircular, with the convexity ectad, but the plate as a whole narrower than long, narrowly acutely incised at the middle line posteriorly, the edges dark, the dark area more extensive on each side of the caudal incision. The blades are slenderly and evenly tapered distad, the distal end strongly curved mesad. The outer left plate of maxillae II has eight teeth, the inner one nine somewhat smaller ones, and the right plate ten teeth which are acute and retrorse and decrease in length gradually and regu- larly proximad. The right maxilla III is a long plate paraUehng II proximally, where it is smooth and edentate, but strongly curved ectad anteriorly and on the curved portion bearing a series of ten erect straight teeth ; the left maxilla II is a shorter, less curved piece bearing only seven teeth. Each maxilla IV bears a single tooth. (Plate 40, fig. 4). The mandibles are small and weakly developed, only slightly chitinized. The masticatory plates are small and transparent, with the edges smooth. The single tube in the collection is incomplete. The part present is 75 mm. long and has a maximum diameter of 5.25 mm. It consists of the usual thin Uning membrane covered with a uniform layer of fine mud. Locality. Off Peru: Sta. 4653 (lat. 5° 47' S., long. 81°24'W.). Depth 536 fms. Bottom of dark brown volcanic mud. Bottom temp. 41.3° F. 12 November, 1904. One specimen in its tube. This species is like mannognathus, sp. nov., and vexillaria Moore in the weak development of the mandibles and in other general structural characters. It may readily be distinguished by the very long first parapodia and in having the branchiae first appear on the sixth parapodia, as well as by other details throughout. It is a much more slender species. 270 THE ANNELIDA POLYCHAETA. Onuphis nannognathus, sp. nov.^ Plate 43, fig. 8-11; Plate 44, fig. 1-5. This species is represented in the collection only by the anterior region of a single specimen. This fragment is composed of one hundred and nineteen somites, so that the number in the complete animal must be very large. The fragment is 64 mm. long, with a maximum width, exclusive of parapodia, of 4 mm., the species being robust. The body is dark brown. On each side just above the parapodia a longi- tudinal band of whitish yellow, which may extend mesad a variable distance in a line along the edge of each somite, and anteriorly on a limited number of somites a median longitudinal white line. Ventrally on each side there is a broad yellowish band running from the fifth somite caudad over the glandular areas at bases of parapodia. The tentacles are dark like the body, but the branchiae and cirri are much paler, being light yellow. The prostomium is very short; subcylindrical, but flattened on the ventral side. Dorsally the usual median longitudinal sulcus is only vaguely indicated. The tentacles are arranged at the circumference of a transverse subelliptic area. Ventrally a median longitudinal sulcus running caudad. The frontal tentacles are prominent, subconical, distally rounded processes which at present are contiguous at base, though, as the specimen seems considerably shrunken, this may not be the condition in fresh specimens. The palps are large bodies contiguous at the middle and elongate transversely. The dorsal tentacles consist, as usual, each of a conspicuous, strongly annulated ceratophore and a long smooth style. The inferior paired tentacles, if stretched back against the body, reach somite IV. The ceratophore of each inferior paired tentacle consists of six or seven very short but strongly marked annuU and a long smooth distal division about one third the total length; it is cylindrical throughout. The style is stout, and is pointed at the tip. The upper paired tentacles reach to or near somite XVII. The ceratophore of each has nearly the same diameter as that of the lower paired tentacles, but it is considerably shorter; it consists of five or six very short, distinct articles, of which the most proximal is largest, and a long, smooth, or but vaguely wrinkled distal division. The style, stout at base, is strongly attenuated distad, the distal portion fine. The median tentacle is equal in length to, or slightly longer than, the upper paired ones. Its ' ub.vvo%, dwarf find 71'aflos, jaw. ONUPHIS NANNOGNATHUS. 271 ceratophore is also of nearly the same thickness and length as that of the adjacent paired ones; it consists of five very short articles, of which the most proximal is somewhat larger than the others, and a smooth distal division which is de- cidedlj^ more than one third of the total length. The style is like that of the adjacent paired ones. The peristomium is much thicker than the prostomium, being conspicu- ously higher, the dorsal surface rounding up from the anterior edge to the caudal. On each side the border protrudes forward convexly and embraces the sides of the prostomium. The lower lip is strongly and abruptly elevated and then sharply set off both laterally and caudally ; the anterior margin is mesally deeply excised, the excision broadly V-shaped, with the outer part of each side curving ectad. The cirri are long and slender, each extending beyond the distal ends of the ceratophores of the tentacles. The first metastomial somite is higher and much longer than the peri- stomium. The second and third metastomial somites are shorter than the first and about equal to each other, and they are high and strongly convex like the first, though the dorsum of the third slopes somewhat downward caudad. The dorsum of the fourth continues the downward slope. At the sixth or seventh somite the minimum depth of the body is attained, the dorsum of these and succeeding somites being only slightly convex and crowned by a shallow median longitudinal furrow. The venter throughout is weakly convex, and is traversed by a conspicuous neural groove. The glandular area, prominent on each side of all but the most anterior somites, is tyj^ically very elongate transversely, with the mesal end narrowed more or less to a point. From about the twenty fifth somite the body narrows forward, the narrowing at the anterior end being very strong; caudad the width remains nearly uniform to the end of the frag- ment. The first somite is about three fourths as long as its greatest width exclusive of the parapodia; the second one half as long as wide; while the twenty fifth and succeeding somites, which, hke all excepting the first few are very short, are about nine times wider than long. The parapodia of the first three pairs are attached at the anterior border near the ventral level and, as usual, are directed somewhat forward, those of the second and thu-d pairs somewhat less so than the first ones. These parapodia are stout, cylindrical, and moderately long. Beginning with the fourth parapo- dia they are attached near the middle of the length of the somite, project trans- versely, and begin a shift dorsad, so that by the twelfth they are at the dorsal level; at the same time the parapodia undergo a decided shortening. In the 272 THE ANNELIDA POLYCHAETA. first parapodia, the notocirrus, attached proximad of the middle, is tapered from the base distad, flattened, and long, extending forward well beyond the bases of the posterior ceratophores ; the nem"ocirrus is attached at the base of the parapodium on the ventral side and is similar in form to the notocirri, but shorter ; in front of the series of setae there is a distinct but short, flap-like, distally convex, presetal lobe, this being much exceeded by the setae, while behind the setae there is a very long cirriform process, about equal in actual length to the neuro- cirrus. In succeeding parapodia the presetal lobe soon quite disappears as such. The postsetal process caudad gradually decreases in length, the distal portion soon being represented only as a short, pointed process from a broad basal flap like the presetal lobe farther forward; and in this form of a thin lobe bearing a short pointed piece distally, the postsetal processes continue to the end of the fragment with no essential further change. The notocirrus is present on all parapodia of the body; but caudad it rapidly becomes reduced and on all but the more anterior segments appears as a slender filament of uniform diameter, or nearly so, throughout its length. The nem-ocirrus continues as a long and conspicuous, tapering process to the seventh parapodia, except that the right seventh cirrus is much reduced in contrast with the left one, which is large ; on the eighth parapodia the neurocirrus is reduced to a slight elevation and thereafter appears merely as merged in a scale in the ventral glandular area. The branchiae begin on the fifth parapodia, each being a single slender, distally pointed filament arising from the base of the notocirri, and about equal- ling the latter in length. On the sixth parapodia the branchiae are similar. On the seventh, each branchia is bifurcate, the two filaments arising symmetri- cally from the base; on the right side one filament clearly exceeds the notocirri, but on the other side there is but little difference. On the eighth and ninth parapodia each branchia is similarly bifurcate, with the filaments but slightly exceeding the notocirrus. The tenth to fourteenth parapodia, inclusive, bear each a trifilamentous branchia, the inner two separating from each other higher up than the primary bifurcation. The next two branchiae have four branches. Following there are branchiae with five filaments and then with six, rarely more, eight being the maximum number observed. (Plate 44, fig. 4, 5). The fila- ments in them arise in an essentially unilaterally pectinate manner, the filaments being at a very acute angle with the stem; they attain or sometimes a little surpass the middorsal line, thus very much exceeding the notocirri. Branchiae continue to the end of the fragment (CXIX somite), in the posterior portion of which the number of filaments is again four, the number that prevails. ONUPHIS NANNOGNATHUS. 273 The acicula proper are colorless; they are much more slender than the crochets, being comparable in thickness to the dorsal setae; a little above the surface from which they emerge, they become strongly narrowed, the tip being slender, acute, and a little curved. The setae of the dorsal fascia are nimierous and conspicuously long and capillary; distally they become reduced to a fine, distally acute, distinctly curved tip; they are scarcely at all limbate, the wings very narrow, short, and usually obscure. (Plate 44, fig. 8). The pectinate setae occur among the capillary setae as usual; they are dehcate, transparent struc- tures, with a long, thread-like stalk, bearing distally a cuneate plate which pro- jects out widely from the axis on one side but remains nearly straight on the other, being thus strongly asymmetrical. The processes of the distal edge are of uniform length. (Plate 43, fig. 11). The crochets are normally two in num- ber, erect, narrowed below the teeth; bidentate, the lower tooth larger and trans- verse, the other one much smaller, proximaUy erect, distally curved outward above the other; fibrillae distinct, extending distad to the base of cervix and a ie-W short ones evident opposite the lower tooth ; the distal ends of the membran- ous guards rise from the lower tooth to an angular tip just above the upper tooth. (Plate 43, fig. 9). On the first parapodium there is a more dorsal group of finely tipped, non-limbate, capillary setae and a ventral group of coarser, composite, distally dentate setae or crochets. In these the joint is moderately distinct. The distal article is short; it is tridentate, the upper tooth short, curved distocephalad, the two lower teeth short, bluntly rounded, the lower- most being shortest; the membranous guard rises but little above the upper tooth. Farther caudad, e.g., upon the sixth parapodia, coarse unjointed setae with a prolonged, flexible, soft, fine tip appear, these a little farther caudad wholly displacing the jointed forms and then themselves disappearing. (Plate 44, fig. 2). Carrier-plate of maxillae I about equal in length and breadth; widening from anterior end to about middle of length, where each side projects in an obtuse angle, and from there the plate narrows to a caudal angle, at the apex of which it is acutely incised. The usual triangular anterior area on each half is distinguishable as a paler region set off caudoectally by a ridge or fold in the plate. The blades are narrowed suddenly at about the end of the first third and again at the end of the second third, beyond which the distal portion is bent strongly mesad; as a whole slender. The right blade in the type has a short tooth or accessory process on the ectal side at the beginning of the distal third. Maxilla II of the right side has nine aciite, in part reflexed, teeth, and one obtuse 274 THE ANNELIDA POLYCHAETA. one at the proximal end of the series, or a total of ten. The right maxilla III is a strongly curved plate presenting a sleiider, straight, edentate arm extending proximad and a curved distal portion bearing a series of nine teeth. The right maxilla IV is a triangular plate in which the anteromesal corner is acute and is turned up as a tooth-like process. (Plate 43, fig. 8). The left maxillae are injiored and partly missing, so that their description cannot be given. The mandibles are small, unusually thin, membranous and flexible, and in general weakly developed; anterior margins meeting at an obtuse angle, smooth and straight; stems weak. Locality. Gulf of Cahfornia: Sta. 3431 (lat. 23° 59' N., long. 108° 40' W.). Depth 995 fms. Bottom of light brown mud. Bottom temp. 37° F. 20 April, 1891. One specimen. This species seems to approach 0. vexillaria Moore, dredged by the Alba- tross off the southern Californian coast at two stations at depths of 243 to 280 fms. (Sta. 4326 and 4401). It is a more robust species with the somites shorter in proportion to length. The branchiae begin on the fifth parapodia instead of on the fourth. The maximum number of branchial filaments is smaller, being six instead of twelve, and the branchiae remain branched as far back as somite CXIX, whereas in vexillaria they have already become unifilar in front of L. The tentacles are longer, the posterior laterals, e.g., reaching somite XVII instead of only to X. In vexillaria the median tentacle is shorter than the posterior laterals, with the ceratophore also clearly shorter, whereas in the present species the median tentacle is longer than these laterals with the cera- tophore equally long. The right maxilla III in the present species has nine teeth as against six in vexillaria. The compound crochets have essentially the same structvire ; but in the ordinary crochets the apical tooth is distinctly longer and more erect and the guard is clearly differently shaped. The distal edge of the pectinate setae is much less oblique. Onuphis litabranchia, sp. nov.^ Plate 50, fig. 7; Plate 51, fig. 1-10; Plate 52, fig. 1. This is a very slender and elongate species which is flattened dorsoventrally and is of nearly uniform width except at the ends where it narrows cephalad and caudad respectively. The type, which is broken into six pieces and is not ' \lTb^, simple, and [ipayix<^, gills. ONUPHIS LITABRANCHIA. 275 wholly complete, has an aggi-egate length of about 167 mm., and a second com- plete but similarly broken specimen has nearly the same length (165 mm.). The greatest width, exclusive of the parapodia, is only 2 mm., the depth varying from 1 to 1.5 mm. The total number of somites counted in the fragments of the type is two hundi-ed and twelve, the number in a paratype two hundi'ed fifty, or above. The general color is yellow, the sides, including parapodia and cu-ri, paler and the nerve cord showing as a narrow, white, median ventral line sometimes appearing broken into spots corresponding to the gangUa. The prostoinium small, very short proximally, subcyUndrical, its outline in anterior view nearly circular, but with lower part of circumference some- what flattened. Its surface is largely occupied by the bases of the seven tenta- cles which are arranged in a circle. The surface encircled by the bases of the tentacles is indented or depressed, the impression being more or less transverse, and the surface below this region protruding forward and bearing the frontal tentacles. The frontal tentacles are very short, broad, flattened dorsoventrally and distally subtruncate, or with distal edge a little incurved. They widen from the base distad, being prolonged distoectally. At the base they are only very narrowly separated, nearly contiguous. The dorsal tentacles all have long stout ceratophores bearing very slender, distally finely attenuated styles. The ceratophores are essentially smooth, only in part obscurely wrinkled and not obviously articulate. The tentacles of the anterior pair reach to or some- what beyond the middle of somite III. In these the style is nearly twice as long as the ceratophore; it is rather abruptly thickened at the base in contact with the ceratophore. Tentacles of the posterior pak reaching somite IX. In these the ceratophore is decidedly longer than that of the anterior. The style is similarly enlarged proximally and is more than three times as long as the ceratophore. The median tentacle reaches upon somite III, or nearly to IV, being of essentially the same size as the anterior paired ones, with cerato- phore and style of similar form and proportions. The enlarged proximal ends of the styles are Ughter in color, whitish. (Plate 51, fig. 1). Peristomium distinctly wider and higher than the prostomium, bulging smoothly outward and upward from its hne of contact with the latter. It is only weakly produced forwards at the sides. Dorsally there is a low median longi- tudinal ridge which at its anterior end projects as a low triangular process against the prostomium, a sulcus running from the tip of the triangle on the prostomium to the base of the median tentacle. The lower hp is set off on each side by a 276 THE ANNELIDA POLYCHAETA. sulcus that runs obliquelv caudomesad; its anterior border is straight and smooth. The cirri are very small, distally pointed processes not reaching the middle of the prostomium or the base of posterior paired ceratophore. (Plate 51, fig. 1). The anterior metastomial region is high, dorsally strongly convexly arched, but ventrally flat. The height rapidly decreases to the fifth (fourth parapodial) somite, caudad of which the somites are strongly flattened dorsally as well as ventrally. The first three podous somites are only rather vaguely separated from each other above; each is widest across the anterior end at level of origin of the parapodia from where it narrows caudad, and is two thirds as long as wide at that level. The fourth somite is abruptly and relatively shorter, the succeeding somites remaining similarly short but gradually increasing a little in width to about the tenth, from where the width does not vary much until toward the posterior end. The fourth, fifth, and irranediately succeeding somites are only about half as long as wide. The intersegmental furrows con- tinue to be faint, excepting laterally, between the parapodia. There are the usual thickened, whitish glandular areas below the level of the parapodia, the integument elsewhere rather thin and semitranslucent. The parapodia in the anterior region are but moderately prominent struc- tures, becoming shorter caudad. They begin on somite II near the ventral level and occupy the same position on III and IV. With somite V they begin a shift dorsad and at somite X they have attained the dorsal level. The first two pairs of parapodia, which are attached at the anterior end of their somites, slope strongly forward. The third parapodia slope forward less strongly and the fourth extend straight out. On the remaining somites the parapodia are attached near the middle of length and are much shortened. The first para- podia are rather stout. Each bears a notocirrus, neurocirrus, and, between these, a setigerous lobe which presents a low and inconspicuous presetal Up and a moderately elongate, subcirriform, postsetal Up which is, however, much shorter than the notocirrus or neurocirrus. The neurocirrus arises on the ventral surface near the base and reaches to or a little beyond the base of the postsetal process. The notocirrus arises on the dorsal surface nearly opposite the nexiro- cirrus; it is constricted at its base, swelling out above this and then tapering to the distal end; it is of about the same length as or but Uttle exceeds the neurocirrus, but it is soniewhat stouter; they fail decidedly of reaching the middorsal line. (Plate 51, fig. 7) . Caudad of the third pair the parapodia proper rapidly decrease in size, and the style or process proper practically disappears. ONUPHIS LITABRANCHIA. 277 The postsetal process is markedly shorter on the second and thu-d pairs, and soon is a mere point and then essentially absent on the ninth parapodia. The neuro- cirrus similarly becomes quickly reduced to a mere nodule and then obliterated. The notocirri continue thi-oughout the length of the body, but in the middle and especially the posterior region have become shorter and much more slender. Branchiae first appear on somite VIII, the first appearance on this somite being uniform so far as observed. The branchiae in the type are throughout undivided, excepting the one case noted below, each consisting of a single fila- ment arising on the dorsal side of the base of the notocirrus. Each of the first branchiae is a slender filament of uniform diameter, more slender than the noto- cirrus but much exceeding the latter in length; it does not reach the middorsal line. (Plate 51, fig. 8). Caudad the filaments increase in length, attaining the middorsal line at or near somite XIII-XV and then a little farther caudad surpassing it, the branchiae of each pair overlapping across the dorsum. (Plate 51, fig. 9, 10). Then the filaments again decrease in size and fall short of reach- ing the middorsal line in the middle and posterior region. The right branchia of the twenty first somite, unlike any other in the type, divides a httle above the base into two branches and one of these, which is somewhat the stouter, again bifurcates toward the tip. In a paratype, however, begmning at somite XXXII, and continuing on about the succeeding fifteen somites, the branchiae are regularly bifilamentous, the bifurcation occurring a Httle above the base; in many of these one filament again bifurcates higher up, or it may have three branches. Caudad of this region the branchiae continue of the miifilamentous fomi as in the type. (Plate 52, fig. 1). The neuropodial acicula seem to be mostly from three to five in number. They are of the same color as the setae, but are much stouter. They first nar- row gradually distad and then more abruptly, the free tips being very slender, long, and acute and commonly more or less curved; they emerge among the bases of the dorsal setae. The notopodial acicula, when detectable, appear as slender, inconspicuous fibers entering the base of the notociriois. (Plate 51, fig. 2). The principal setae of the dorsal fascicles are long, slender, and of uniform diameter until toward the distal end, where they narrow to a very slender, fine, and acute tip, the narrowing portion of the setae being ordinarily cm-ved, the fine tip more strongly so; each of these setae is distinctly bilimbate, each wing rather narrow, beginning a Httle proximad of the narrowing region of seta and continuing distad to fade out on base of the fine tip. (Plate 51, fig. 3). Among 278 THE ANNELIDA POLYCHAETA. the bases of these hmbate setae are the delicate, transparent, and inconspicuous pectinate forms ; these are few in number and extend but little beyond the level of the tips of the crochets in the segments where these are present ; the end- piece of these is asynmietrically, narrowly cuneate in form, one edge being prolonged. (Plate 51, fig. 4). The crochets in each parapodium where present are two in number; each is stout, with the usual double curve, and is distally bidentate ; of the teeth the apical or one on convex side of the neck is acute, with sides nearly straight, or the inner side a little convex and the tip of tooth slightly bent inward; the other is much stouter with sides similarly straight and its apex on a level with that of the smaller one and its outer edge parallel with that of the latter; the guards extend over and somewhat above the teeth. (Plate 51, fig. 5). The crochets begin on the thirteenth somite (twelfth para- podium). On the first and a few succeeding parapodia there are a few larger setae of the hooded crochet-type ; these are moderately long and a little curved distad; each is bidentate, a single smaller accessory tooth lying considerably below the large, nearly erect, distal one; the guards are conspicuously prolonged, each being slender and with a fine tip. (Plate 51, fig. 6). On the immediately succeeding somites these crochets seem to be replaced by finely tipped, untoothed setae. The maxillae are thin and mostly pale, dark pigment occurring on the bor- ders adjacent to the suture between blade and carriers and that between the halves of the latter in maxillae I, and along the dentigerous borders of the other maxillae. Maxillae I have the carrier-plate narrowing from the anterior end caudad, i.e., its posterior portion subtriangular, the caudal angle mesally narrowly incised; each blade is conspicuously curved distally in the usual way, and is broad proximally, but slender distally, where also it is somewhat darkened. Maxilla II on the left side in a paratype has eight long, slender, acute, and more or less retrorse teeth along its inner edge, the untoothed proximal edge short. The unpaired plate, which lies close to this plate within and parallel to it, bears nine similar teeth. The right maxillae II appears to bear the same number as the left, eight, though it is broken in the preparation examined, and one or more additional teeth may have been present. The left maxilla III bears four slender, acute teeth, the right seven. Maxillae IV with a single tooth. (Plate 50, fig. 7). The mandibles are comparatively small, thin, and delicate; the masticatory plates are narrow and elongate, their anterior edges minutely crenulate but not truly dentate, very oblique, their projections meeting mesally at an angle of about forty-five degrees; the stems rather slender and short, diverging caudad. ONUPHIS PACHYTMEMA. 279 Locality. Off :Mexico: Sta. 3415 (lat. 14° 46' N., long. 98° 40' W.). Depth 1,879 fms. Bottom of gi-een mud. Bottom temp. 36° F. 10 April, 1891. Several specimens. This species has a number of sinularities to 0. nehulosa Moore secured in Monterey Bay in much shallower water (65-71 fms.). In the latter species the gills begin similarly on somite VIII (or IX) and are largely simple, with bifilamentous ones frequent and a maximum number of fom* filaments; however, more of the gills seem to be divided and the longest of them just reach the mid- dorsal Une instead of passing much beyond it. The anterior parapodia are longer. The postsetal process of the parapodia undergoes reduction much more gradually. The anterior crochets differ in ha^'ing two accessory teeth instead of but one and noticeably in lacking the conspicuous prolongation to the guards. The posterior crochets differ perceptibly in having the lower teeth directed more nearly at right angles to the axis and making a decidedly larger angle with the apical tooth. The ceratophores of the dorsal tentacles differ in being distinctly quadriannulate. The maxillae are very sinular in general appearance; the teeth of maxillae II are more numerous (ten instead of eight), and the left and right maxillae III have six and eight teeth respectively instead of four and seven in litabranchia. OnUPHIS PACHYTMEMA, Sp. nOV.^ Plate 48, fig. 5-11; Plate 49, fig. 1-8; Plate 50, fig. 1-6. The_ general color is light brown, with a pale ventral neural stripe showing enlargements corresponding to the ganglia and also a fight median longitudinal dorsal stripe excepting anteriorly; below each parapodium is a swollen, whitish glandular area; the cirri are pale. A complete specimen in one piece was not secured. Tliree fragments of one specimen had a total of eiglity-five somites and together measured 85 mm., the maximum width being 3 mm. A second specimen, also in three fragments, had also eighty-five somites, or very close to that number, a total length of 98 mm. and a maximum width of 3.25 mm. The body seems thus to be proportionately stout and rather short, widest in the middle region, where the width is nearly uniform, and narrowing at the ends, less conspicuously so at the caudal. The body is low, being compressed dorsoventrally. The prostomium is somewhat hemispherical and is circular in outUne in ' naxi'i, coarse, riirja, segment. 280 THE ANNELIDA POLYCHAETA. anterior view. It is depressed anteriorly between the bases of the frontal tentacles and is vaguely, finely, transversely wrinkled above between the poste- rior tentacles and the peristomium, and there is a weak median longitudinal sulcus between base of median tentacle and the caudal margin. The bases of the tentacles are arranged in a circle. The frontal tentacles are subconical, distally well-rounded processes, also constricted at very base, diverging from each other moderately and separated at their bases typically by about half their diameter; the prostomium beneath these is but slightly carried forward. The frontal tentacles have the usual long, stout ceratophores bearing the slender, finely attenuated styles. The ceratophores are aU wdest near the middle, narrowing toward both ends, and are composed of numerous very short annuli between which the constrictions are not deep or conspicuous. The tentacles of the anterior pair reach a little caudad of the middle of somite II. In these the style is twice as long as the ceratophore and is uniformly narrowed distad; the ceratophore is composed of seven very short annuli, of which the most distal is longest. The tentacles of the posterior pair reach to somite VII. In these the style is between five and six times as long as the ceratophore. The cerato- phore is fully a third longer than that of the anterior pair and is much stouter; it consists of nine or ten very short articles, of which the ultimate is longer than the immediately subjacent ones, as usual. The median tentacle is much shorter than the posterior laterals, reaching only to about the beginning of the third somite. In this the slender style is nearly three times as long as the ceratophore. The ceratophore is much more slender and only about tliree fourths as long as that of the posterior laterals; it is composed of five articles. (Plate 49, fig. 5). The peristomium laterally continues the general outline of the prostomium, widening caudad. It is more abruptly elevated dorsaUy. The anterior margin above is angularly produced forward at the middle. Laterally the anterior margin is nearly straight. On each side a weak furrow runs back obhquely caudoventrad. The lower lip is strongly elevated; it is set off on each side by a depression running obhquely caudomesad from the outer anterior angle; its anterior margin is smooth, and widely, moderately incurved mesally. The tentacular cirri are short, slender, acuminate processes attached near the ante- rior margin and not reaching to base of the posterior tentacles. (Plate 49, fig. 5). The first two metastomial somites are strongly arched dor sally, the third decreasing in height caudad to the distinctly lower level of the immediately following somites. The peristomium is longer than the first podous somite, ONUPHIS PACHYTMEMA. 281 but is decidedly shorter than the first two together. Each of the first three metastoniial somites is widest across the anterior end at the level of attachment of parapodia, narrowing to the caudal end. The length in these is about three fifths the greatest width. They are only obscurely marked off from each other dorsally. The third is separated from the fourth by a sulcus more distinct than that between those either in front or immediately caudad. The somites of the posterior median and caudal portions of the body are very distinctly separated above as well as laterally and ventrally. The fourth somite is much shorter and is two and a half times wider than long. From here caudad the somites increase in width to near the tenth, thereafter remaining more nearly uniform to the caudal region. The somites near the tenth are twice or a little more as wide as long. In this region they are decidedly flattened dorso ventrally, the dorsum being but weakly arched and the venter flat. The dorsum is some- what more highly arched again in the posterior median region. The somites present the usual whitish, transversely elongate, swollen glandular areas below the parapodia. The parapodia of the first three pairs are moderately prominent and project obliquely forward. They are attached at the anterior border of their respective somites near the ventral level. With somite V (fourth pair) they begin to be shifted dorsad, and at somite IX they have attained the dorsal level and at the same time have had the bases shifted back from the anterior border and are greatly shortened. The fourth parapodia project less strongly forwards and the succeeding ones extend out nearly horizontally. The first parapodia are stout. Each bears a notocirrus attached near the middle dorsally, a neuro- cirrus attached farther proximad on the ventral surface, and is distally extended into the setigerous neuropodial lobe which presents a conspicuous, cirriform, postsetal process. The notocirrus is slenderly tapered from the base as usual; it reaches less than halfway to the middorsal line ; the cirrophore is low. The neurocirrus is similar in form to the notocirrus, but is somewhat shorter. The postsetal process does not extend out quite to the level of the tip of the noto- cirrus. (Plate 48, fig. 5). In succeeding parapodia the notocirri continue to the last, but decrease gradually in length and become much more slender, with the base in the anterior ones more constricted. The nem-ocirrus is much shorter on the second parapodia and on the third is but a rather short, conical body; on the fourth parapodia it is reduced to a low, rounded prominence and on suc- ceeding somites it is a simple plate merged with the glandular swelling. The postsetal process is much reduced on the second and third parapodia and by the 282 THE ANNELIDA POLYCHAETA. ninth has been reduced to a mere low, obtuse, angular projection and is not evident on the following ones. The presetal margin is not in any case especially elevated. (Plate 48, fig. 6, 7). The branchiae first appear on the sixteenth parapodia, i.e., on those of the seventeenth somite. Each of the first branchiae consists of a single rather stout filament a little exceeding the notocirrus in length. (Plate 48, fig. 8). The second branchiae are bifurcate, with the filaments either equal in length or one exceeding the other, or trifilamentous. The third and succeeding branchiae to about the seventeenth are mostly trifilamentous, a long filament arising on the anterior side close to the cirrus and making an angle of about forty-five degrees or more with the other branch, which bifurcates farther distad, the branches being either subequal or, more commonly, the caudal one smaller, often much so; rarely a branchia occurs with four branches. (Plate 48, fig. 9, 10; Plate 49, fig. 2). Caudad of this region the branchiae become mostly bifilamentous, one branch being greatly elongated and the other more and more reduced. (Plate 49, fig. 3, 4). In the posterior region the branchiae consist of a single slender fila- ment which undergoes gradual reduction until represented by a mere nodule and finally quite disappears at about the twenty fifth somite from the caudal end. (Plate 48, fig. 11). In the region of the twentieth and immediately follow- ing somites the branchiae reach the middorsal line; at the thirtieth, and imme- diately following, the long filament passes beyond the middle line. The dorsal setae of the anterior parapodia are slender and capillary, distally acutely acuminate, and not at all limbate. The setae of the dorsal group of the other parapodia are long, slender, and gradually reduced distad to a very fine tip; they are normally curved distally and each is hmbate in the usual way, a narrow wing on the side of the convexity in the curved distal part beginning near or below the middle of the exposed portion of the seta and continuing to the base of the bristle-like tip. (Plate 50, fig. 4). The pectinate setae occurring among the bases of these limbate setae are short and delicate structures which are large comparatively; distally each is clavately enlarged, the cuneate apical piece being long, narrow, and asymmetrically prolonged distally on one side, as usual. (Plate 50, fig. 5). The ordinary crochets first appear on or near the tenth somite and occur on succeeding ones to the last of the series, there being normally two in each parapodium ; they project more prominently in the poste- rior region. In the posterior region they are stout, naiTowed distad, and biden- tate at the tip; the apical tooth is very small and erect, the other much larger one projects nearly at right angles to it and has its very tip bent distad, its ONUPHIS PACHYTMEMA. 283 upper surface being slightly concave. The membranous guards rise broadly a little above the teeth. (Plate 49, fig. 8). On the first three parapodia there are elongate jointed crochets, the articulation being far distad, and the second article short; distally the second article is bidentate, the subapical tooth small; the guards extend much abor\'e the level of the teeth and are narrowed gradually to a slender acute point distally. (Plate 50, fig. 1). These are replaced on the fourth parapodia, etc., by coarse setae which are drawn out distally to a fine point and may or may not show an imperfect jointing. (Plate 50, fig. 2). The ordinary ventral setae are finely pointed, distally curved, and narrowly shortly limbate on the convex side. (Plate 50, fig. 3). The acicula are of the typical form, each narrowing strongly at the distal end, and the protruding portion fine, subcapillary, and curved. (Plate 50, fig. 6). The maxillae are rather thin, light brown in color, with black edging. Max- illae I have the plate formed by the carriers narrowed across the anterior end, below which it bulges convexly on each side to narrow again caudally; there is an open V-shaped median incision from the caudal margin; an inverted, tri- angular anterior area on each half is thicker, as usual. The blade of each maxiUa is proximally very broad, being abruptly much narrowed distad of the middle in a characteristic way. (Plate 49, fig. 6). Maxillae II have the left paired piece bearing ten teeth; the unpaired plate has also ten teeth, with a smooth proximal edge longer than that of the paired plate. The right maxilla II has the distal process narrower and tooth-like, being curved mesad like the other teeth with proximad of it ten teeth, making the full number of teeth eleven. (Plate 49, fig. 6) . The number of teeth on maxillae III was not ascertained. The masticatory plates of the mandibles are large and obliquely elongate, with the distal angle subacute. The anterior edges of the plates meet mesally at an angle of less than ninety degrees; they are straight and smooth except for a single acute incision at about the middle of the length of each. There is a short incision on the outer end in the usual position. Especially on the caudal half of each plate striae parallel to the caudal margin are pronounced. The two plates are broadly in contact mesally. The stems taper and diverge caudad; they show striation rather distinctly. (Plate 49, fig. 7). Of the several tubes the longest measiu-es near 460 mm., with a maximum diameter of 5 mm. The inner tube or fining consists of a tough, whitish, trans- lucent membrane over which is the layer of fine, closely adhering mud, which is dark greenish grey in color. Locality. Off Peru: vicinity of Sechura Bay. Sta. 4658 (lat. 8° 30' S. 284 THE ANNELIDA POLYCHAETA. long. 85° 30' W.). Depth 2,370 fms. Bottom temp. 35.3° F. Several tubes with spechnens in situ were dredged 14 November, 1904. This species is clearly a very close ally of 0. ehlersi and 0. armandi of Mc- intosh which were secured by the Challenger expedition off the Chilean coast at a depth of 2,225 fms. and midway between Kerguelen and Melbourne (53° 55' S. and 108° 35' E.) at a depth of 1,950 fms. From ehlersi it differs in general appearance, apparently, in being a decidedly shorter and stouter form with the somites longer. It differs uniformly in having the branchiae begin on the sixteenth parapodia instead of on the seventeenth, and in the greater length of these, many of which in the present species pass beyond the middorsal line, with the cirri relatively veiy small. Mcintosh's figure shows the peristomium as shorter than somite II; in the present species the reverse is clearly the case. His figures show the carrier-plate of maxilla I to be proportionately broader and shorter and the blade to be less strongly narrowed distad of the middle. The anterior articulate crochets differ in details. The blade of the pectinate setae is relatively shorter, much broader, and less symmetrical. From 0. armandi the species differs in having the brancliiae more strongly developed, trifilamentous brancliiae occm-ring prevaiUngly from the nineteenth to the thirty fifth parapodia, whereas in armandi on the twentieth and thirtieth parapodia the branchiae are only bifilamentous and at the fortieth part have become reduced to single filaments. In armandi the fu-st branchiae are bifilamentous, but in present species are uniformly simple. The carrier-plate of maxilla I is relatively very much shorter, that of armandi being but Uttle shorter than the blades. The species differs from both of these species of Mcintosh in having the anterior edge of the mandibles smooth excepting for a single acute incision. The carrier-plate of maxilla I is much shorter and the blade more abruptly narrowed distad. The setae differ in details, the pectinate setae, e.g., having the distal expansion relatively much shorter and broader. Onuphis socia, sp. nov.^ Plate 47, fig. 1-11; Plate 48, fig. 1^. The general color is dilute brown of a pronounced green tinge; a paler middorsal and midventral longitudinal line, which may be discontinuous and not evident anteriorly, is more or less developed. The type. Station 4672, the maximmn specimen, has a length of 86 mm. 1 socius, associated. ONTPHIS SOCIA. 285 and a maximum wadth of about 3.2 mm. It is composed of about one hundred and forty-five somites; but a large parat^^De from Station 4666 is 178 mm. long, and, though its width is the same as in the type, the number of somites is two hundred and seven. The prostomium is short and subcylindi-ical, being slightly narrowed anteriorly and in anterior view circular in outhne. Above it presents a median longitudinal fmTow from the base of the median tentacle caudad; and in front the area within the base of the tentacles is flattened. The tentacles are arranged in a circle. The frontal tentacles are short, subcyUndrical processes subconically rounded distad and sometimes a httle constricted toward base; they are separated by rather less than half their diameter; the prostomium beneath them is but slightly carried forward. The frontal tentacles, as in alUed species, consist each of a long ceratophore bearing a much more slender, finely attenuated style. The ceratophores are nearly strictly cyhndrical and are strongly and closely annulate, the annuU being short and numerous, the con- strictions separating them distinct, but often not deep. The tentacles of the first pair reach to the anterior half of somite II, their tips attaining the bases of the first parapodia, or in some cases reach toward the caudal end of the somite. In these the style varies from rather less than twice as long as the ceratophore to somewhat more than twice as long. The ceratophore in the type is composed of five annuli of which the most distal is longest and the two immediately proxi- mad of it the shortest. The posterior paired tentacles in a paratype reach to somite VII, which is probably the usual proportionate length, but in some appear shorter. In the type they do not extend beyond somite III. The ceratophores are longer and much stouter than in the first pair; each is composed of six articles of which the most distal is longest and the three preceding it are shortest and subequal to each other; in the larger paratype from Station 4666 the ceratophore is composed of nine articles, the very short additional rings being found adjacent to the distal one. The median tentacle, as in others of this group of species, is much shorter than the adjoining posterior laterals, reaching only to the third somite. Its ceratophore is decidedly shorter than that of the posterior laterals, being about equal in length to that of the anterior laterals, though decidedly stouter; it is composed of five annuU, of which the most proximal and most distal are longest. The palps are large, conspicuous bodies, stout, and subcontiguous at the median line and conicaUy narrowed distad, the two diverging from each other, the axis of each extending ectoventrad. 286 THE ANNELIDA POLYCHAETA. The peristomium is longer and wider than the prostomium, its anterior border above and laterally being rounded down to the surface of the latter. It is a little longer than somite II (6:5 in type), or sometimes equal to it. Its surface dorsally and laterally is smooth. Down its anterior slope above there is a median elevation that projects triangularly against the prostomium in the usual way. On each side the margin protrudes forward broadly, convexly to embrace the prostomium. The lower Up is set off on each side by a deep and wide furrow extending from each side but little caudad of ventrad; its anterior margin as a whole is convex, but at the middle is conspicuously excised, the bottom of the excision straight, with a short sulcus running from each end of it obUquely caudoectad. The cirri are short acuminate processes reaching to or but slightly beyond the nearest point of the base of the corresponding posterior lateral tentacle. The first three metastomial somites form a more or less sharply separated division of the body, characterized by a high, strongly convex dorsum, the fourth somite being very much lower, and the third somite dorsally sloping from the level of the second to that of the third. Caudad of the fourth somite the depth of the body again gradually increases, but caudad of the anterior third again becomes less, the body in the middle and posterior regions appearing typically decidedly flattened. The first metastomial somites are widest across the anterior end, as usual; the first in the type is two and a half times wider than long; the second is longer, in the type a Uttle less than half (2.4:5) as long as wide, the third is also of about the same proportions. The fourth metastomial somite has the proportions of the first, being two and a half times wider than long. In a paratype these first parapodia-bearing somites have the same length and proportions. The somites from the fourth caudad are distinctly separated above as well as laterally and ventrally. The somites increase in width to about the fifteenth, then again narrow a little and remain nearly uniform over the middle region, though the caudal region gradually narrows, with the caudal end more abruptly acutely pointed. The fifteenth somite and adjacent ones, measured across between bases of parapodia, are nearly four times as wide as long, the somites in this and the following region being very short. The dorsum over the somites caudad of the fourth is marked by longitudinal sulci, one each side of the middle; between these the area tends to be Ughter in color and the anterior edge j^rotrudes forward more or less and may appear notched where crossed by each sulcus. There is a similar double sulcus along the ventral surface setting off a neural stripe, with a slight median protrusion of the anterior ONUPHIS SOCIA. 287 edge in each somite. The pygidium is a small, subconical body; the cu-ri are broken off. The parapodia of the first three metastomial somites are, as in other species of this particular group, attached near the ventral level. They are moder- ately prominent and usually project forwards, though there seems to be some variation in this regard. The first parapodia are attached at the anterior border of their somite, the second and third farther caudad. The fourth para- podia are attached at the middle of the length of their somite, and they project more nearly directly outward. Beginning with this jjair the parapodia begin to shift farther dorsad and at the seventh or eighth pair have reached near the dorsal level. At the same time they have become decidedly shortened and now project dorsad or a little ectad of dorsad. The fu'st parapodia are moderately stout. Each bears a notocirrus, attached at its base above, which is proximaUy swollen out above a somewhat constricted base and is then uniformly tapered to an acute tip and is rather long, reaching, when the tip is unworn, to the anterior edge of the peristomium and clearly more than halfway to the mid- dorsal line. The neurocirrus is attached nearly opposite to the notocirrus and is similar in form, though shorter. The setigerous process is bluntly rounded, subhemispherical ; it presents a low presetal lip and a long, cirriform, distally tapering postsetal process nearly as long as the neiirocirrus, but proximally more slender. In succeeding parapodia, apparently to the last, the notocirrus continues, but becomes shorter and very much more slender and filamentous. The neurocirri on the second and third parapodia are similar in form to those on the first, but those of the third pair are much smaller. (Plate 47, fig. 7). On the fourth parapodia the neurocirri have abi*uptly changed to a mere flattened scale and are here and on subsequent somites, therefore, essentially absent as any distinct process. (Plate 47, fig. 8) . The postsetal process gradually decreases in size caudad, becoming finally merely a slight conical process and not at all evident as a distinct elevation caudad of the twelfth parapodia. The first branchiae occur uniformly on the seventeenth parapodia {i.e., somite XVIII), though in one specimen the branchia appeared only on one side (the right). The branchiae seem not to occur in most specimens examined beyond the fifty fifth parapodia and in one ceased at the forty fifth, while in another they were traced to the sixty first. Thus, while the point of beginning is fixed, that of ending is variable. The first branchia, are usually simple, but in fewer cases are bifilamentous or even trifilamentous on one side. (Plate 47, fig. 9). The second branchia in one specimen is undivided on the right 288 THE ANNELIDA POLYCHAETA. side and trifilamentous on the left ; in another it is undivided on the right and bifilamentous on the left; and in the type it is bifilamentous on both sides, the branchiae, as in the case of the first ones, clearly exceeding the notocirri. (Plate 47, fig. 10). The thu'd branchiae in the type are trifilamentous, but in two other specimens examined are symmetrically bifilamentous. (Plate 47, fig. 11). The fourth branchiae in the type have four filaments on the left and three on the right, the branching being arborescent ; in two other specimens they are simply bifurcate. In the type the fifth branchiae on the left side has three filaments, on the right four, the branching arborescent as usual; in the other specimens each branchia has three filaments. (Plate 48, fig. 1). In the type the sixth branchia on the right side has four branches, the left one missing; a second specimen has four filaments on the left and three on the right. The seventh and eighth branchiae of the left side have three filaments, the right missing; the ninth three on each side, the tenth and eleventh four. (Plate 48, fig. 2) . On the left side in the type the twelfth left branchia has two filaments of which one is much more elongate than the right, the thu-teenth thi-ee, of which the middle one is greatly elongate, and, when laid back against the body passes beyond the middle line of the dorsum. (Plate 48, fig. 3). The fourteenth also three, with the middle one similarly elongated. The eight branchiae following this are mostly similarly trifilamentous. The following ones are almost all unifilamentous with the filament long, reaching or surpassing the middorsal line or, when laid forward, as they seem to be normally, attaining the third and sometimes the fourth preceding somite (Plate 48, fig. 4) ; caudad these decrease, but in the last detected (fifty fourth somite) they are still decidedly longer than the notopodium. The acicula in the anterior parapodia are slender, distally reduced to a fine tip and scarcely as thick as the dorsal setae, and more slender than the ventral setae; their tips scarcely protrude. In the posterior region the acicula become stouter and the fine tips protrude as usual. (Plate 47, fig. 6). In the first three pau's of parapodia the dorsal fascia are capillary, slenderly acuminate, finely tipped, and not hmbate. The coarser ventral setae in these parapodia are compound, the joint distinct and well toward the tip; in these the tip is bidentate, the apical process or lobe is large and rounded, the subapical very small, acute, and close to the apical lobe; farther proximad there is a slight shoulder as in the preceding species; the membranous guards narrow distally to a slender point and rise much above the upper lobe. (Plate 47, fig. 3) . Farther caudad the dorsal setae become longer; they end distaUy, as usual, in a very ONUPHIS SOCIA. 289 fine curved tip; below the tip the setae are biUmbate. (Plate 47, fig. 4). The crochets are two in number; they are stout and have the usual slight double curve distally; they are bidentate, the apical tooth being very small and erect, the other one much larger and stouter, its upper edge nearly straight, its lower convex ; the guards rise very slightly above the teeth and have the upper margin straight or slightly incurved, long. (Plate 47, fig. 5). The pectinate setae are strikingly different in form from those of the preceding species; from a delicate fine stalk each very gradually widens distad, the enlarged blade being unusually long and slender, and the setae as a whole somewhat oar-shaped. The maxillae are thin and mostly transparent, of a weak brownish tinge. Maxillae I have the carriers forming a plate which is broad in proportion to its length; the thickened triangular areas extend to the caudal incision, where their acute apices end in contact; the thin plate caudoectad of this on each side has the general form usual in this group of species, but it does not bulge posteriorly, the lateral edge in front of the widely rounded caudal corner being straight or diverging a little cephalad from the long axis. The blade on each side is proximally veiy broad; it is abruptly narrowed well distad of its middle, the narrowed fang being shorter than in the preceding species. Maxillae II are long, narrow plates bearing on the right side thirteen acute and more or less retrorse teeth, the most caudal of which is nearly at the caudal end; on the left side the inner plate bears twelve teeth, the outer one, which lies close against and parallel with the inner, bearing thirteen teeth. Maxillae III of the left side bears eight teeth (or nine counting an obscure prominence at the proximal end of the series) in a short, very slightly curved row, the right one bearing eleven in a strongly cui'ved row. (Plate 47, fig. 2). The mandibles in the type have the masticatory plates hard and white, oblique, with the inner ends much prolonged caudad and subacutely pointed; the anterior margin has a single acute incision only, or with trace of a second one. The stems are rather broadly united anteriorly; they are slender and unusually long, and do not narrow caudad until near the caudal ends. (Plate 47, fig. 1). In the tubes the maximum length noted among those from Sta. 4672 was about 400 mm., the maximum diameter 5 mm., while some tubes were but 3.5 mm. in diameter. The tubes have a tough, though thin, whitish lining membrane outside of which is the thick layer of fine mud, which is greyish brown in color but in part may have a slight greenish tinge. A tube from Sta. 4666 is 455 mm. in length. Locality. Peru: off Palominos Light House. Sta. 4672 (lat. 13° 11' 290 THE ANNELIDA POLYCHAETA. S., long. 78° 18' W.). Depth, 2,845 fms. Bottom of fine dark brown infusorial mud. Bottom temp. 35.2° F. About fifteen tubes, in part with animals in situ, were secured 21 November, 1904. Off Peru: Sta. 4666 (lat. 11° 51' S., long. 84° 20' W.). Depth 2,600 fms. Bottom of fine grey radiolarian ooze. Bottom temp. 34.9° F. Two specimens in tubes taken 18 November, 1904. This species is close in general structure to 0. pachytmetna. It differs clearly, however, in a number of features. It contrasts in its decidedly greenish color, and equally conspicuously in its very much shorter somites. It differs uniformly in having the branchiae begin on the seventeenth parapodia instead of on the sixteenth. The ceratophores of the tentacles lack the narrowing towards both ends from the middle region characteristic of pachytmema, these being strictly cylindrical, or with the sides at least not curved longitudinally. The palps are more conical. The carrier-plates of maxillae I are relatively broader, not incurved anteriorly, and have the thickened area extending to the caudal incision instead of only part way, and the narrowed distal fang of the blades relatively shorter. Maxillae II have twelve and thirteen teeth as against ten. The mandibles have the masticatory plates more prolonged caudad along the median line and the stems longer. The pectinate setae differ decidedly in form, the distal blade being very much longer and narrower. The lower prong in the crochets is longer and straighter. From 0. ehlersi Mcintosh, which it also approaches, it would seem to differ decidedly in general form, being much shorter and broader, its maximum observed length being 86 mm., with a maximmn diameter of 3.4 mm., whereas in ehlersi the average length is 170 mm. and the width 2.5 mm. The carrier- plates of maxillae I differ in not being narrowed anteriorly and the blades in having a shorter and a more abruptly narrowed distal fang. The teeth" of maxillae II are twelve and thirteen instead of ten; and the teeth of maxillae III are eight on the left side and eleven on the right in place of nine on both sides. The pectinate setae have the distal blade clearly relatively longer and more slender. The branchiae would seem to be more strongly developed. Onuphis lepta, sp. nov. ^ Plate 45, fig. 1-7; Plate 46, fig. 3-12. The general color is brown, without definite markings excepting a paler, ventral neural fine which is ordinarilv traceable over much of the length. The appendages are scarcely paler. ' Xeirris, slender. ONUPHIS LEPTA. 291 All the animals were preserved in situ in their tubes, their posterior portions being, in consequence, soft and in poor condition. They were removed with difficulty, and no animal was secured entire. One specunen in several pieces, but not fully complete, embraced about one hundred and thu-ty-eight somites; the most anterior piece, consisting of the head and seventy somites and meas- uring about 70 mm. in length; the somites thus being long. The combined length of the pieces of this specimen is near 150 mm. The greatest width, exclusive of the parapodia, is 2.6 mm. The maximum diameter of the type is 3 mm. The prostomium is short, cyhndi-ical, rounded distally, and somewhat flattened between the bases of the tentacles. Dorsally there is the usual median longitudinal sulcus from the base of the median tentacle caudad ; and ventrally the surface just caudad of the frontal tentacles is concavely depressed. The tentacles are arranged in a cu-cle. The frontal tentacles are small, proportion- ately stout, subcorneal, distally rounded processes separated at the base by about half the basal diameter and strongly diverging from each other distad, each projecting ectoventrad. Each dorsal tentacle consists of the usual stout annulate ceratophore and a long, slenderly subulate, smooth style. The cera- tophore of the anterior paired tentacles is composed typically of four annuU; the style may be as much as fom- times as long as the ceratophore, reaching to the fourth somite. The posterior paired tentacles reach to the anterior border of the seventh somite. The ceratophore is from a fourth to nearly a half longer, and is decidedly stouter than that of the anterior pair. It is nearly cylindrical, but thicker distally than proximally, and consists typically of eight amiuU, of which the most distal is longest. The style becomes very fine distad and is six times, or somewhat more, longer than the ceratophore. The median tentacle reaches to the third somite, being thus considerably shorter than the anterior laterals, and veiy much shorter than the posterior laterals. The ceratophore is nearly equal in length to that of the anterior paired tentacles, or it may be a little shorter to considerably longer ; but it is much stouter as a rule, though in thickness also varying considerably; it is somewhat narrowed distad, and con- sists of four articles. The style in the type is nearly four times as long as the ceratophore. The palpi are of moderate size, spherically rounded, and con- tiguous at the middle line. (Plate 45, fig. 1). The peristomium is longer and abruptly thicker than the prostomium, and above it rises conspicuously from its anterior to its caudal border. The dorsal surface is smooth. The anterior margin above curves gently forward from the 292 THE ANNELIDA POLYCHAETA. sides to the middle, but there is no normal triangular process at the middle. On each side the border protrudes forward to embrace the sides of the pro- stomium; the margin of the protrusion is semicircular. From near the anterior border on each side the usual furrow curves ventrad and then more caudoventrad. The lower lip is conspicuously elevated, each of its anterolateral corners being high, free, and rounded; from each of these free corners the anterior margin runs caudad of mesad, as a whole forming a conspicuous obtuse angle, but with the margin a little more depressed at the middle ; the surface of the Up is smooth. The tentacular cirri are small, pointed, pale appendages scarcely reaching beyond the caudal edge of the base of the posterior paired tentacle. (Plate 45, fig. 1). The first metastomial somite continues smoothly the outline of the peri- stomium above, its depth being thus clearly greater; and it is also much longer than the peristomium. The depth of the immediately succeeding somites decreases gradually and evenly to the sixth and seventh, where the dorsoventral thickness of the body is least. The second metastomial somite is shorter than the first, the third than the second, and the fourth than the third, after which the lengths are gradually increased again. As the somites decrease in height they become less and less strongly arched above, the somites from near the sixth caudad being but slightly convex above and being sharply separated from each other by a distinct line, while the more anterior ones are but vaguely separated dor sally. Ventrally the somites are nearly flat, so that the body over most of its length presents a flattened appearance, the dorsoventral diameter being small in comparison with the width. The first metastomial somite is about five eighths as long as the greatest width across the anterior region; and the fourth two fifths to three fourths as long. At the twenty fifth metastomial somite the length has again increased until it is more than half the width {e.g., dr. 11:20). The pygidium was not detected. The parapodia of the first pair project strongly forward, as usual, the noto- cirri sometimes extending forward about as far as the tips of the tentacular cirri, or nearly to the posterior level of the lower paired tentacles. The second parapodia extend less forward, the third still less, whUe the fourth and succeeding ones are essentially transverse. The parapodia of the first three pairs are attached near the anterior edge of their somites and near the ventral level ; begin- ning with the fourth, the parapodia are attached near the middle of the length of the somite and begin to shift gradually dorsad, and with the seventh pair have reached the dorsal level. The notociiTus of the first parapodium is attached near ONUPHIS LEPTA. 29:} the base about as usual; distad of the short, cylmdrical paler cirrophore it expands abruptly, then narrowing gradually to a point. The neurocirrus is attached, as usual, on the ventral surface at the base; it is shorter and more slender than the notockrus. The low, distally rounded setigerous lobe is not extended in front of the setae, but it is produced into a slender cu-riform post- setal process, which is much shorter than the cirri proper, commonly not more than half as long as the notocirrus. (Plate 46, fig. 3). In succeeding parapodia the notocirrus continues throughout, but caudally becomes much reduced both in length and thickness. The neurocirrus of the second pair is shorter than on the first, and "that of the third is still shorter, often appearing as a short, basally stout, conical process; that of the third and succeeding parapodia appears only as a flattened scale merged in a ventral glandular area. The postsetal process becomes quickly reduced caudally but appears as a short subcorneal process as far back as the seventh, or sometimes the eighth parapodia, caudad of which it is obhterated. (Plate 46, fig. 3-8). The branchiae first occur on the sixth parapodiferous segment and continue to the fifty third inclusive. They are in all cases simple, unbranched filaments. (Plate 46, fig. 9-12). The ordinary acicula are proximally stout, but distally they are strongly attenuated, the tip being very fine and often sinuously curving. (Plate 45, fig. 7) . In the ordinary somites of the middle and posterior regions there are the usual types of setae. The setae of the more dorsal group are of moderate length, flattened, distally more or less curved, with a fine tip, and distinctly narrowly Imibate. The delicate pectinate setae are relatively large; distally they enlarge clavately very gradually, the expanded distal portion being comparatively long and moderately narrow; the distal pectinate end is asymmetrical, rising obliquely from one side to the other, with teeth apparently of uniform length. (Plate 45, fig. 5). The somite at which the ordinary crochets begin in the type is the eleventh (tenth parapodial). In each parapodium they are usually two in number, but sometimes three occur. They are stout, rather strongly narrowed just below the teeth; bidentate, the inferior tooth large, acute, straight, or with the tip slightly bent downward, and projecting forward about at right angles to the general axis of the crochet ; thfe superior tooth much smaller, acute, and bent forward but httle. The membranous guards extend distinctly over and above the inferior tooth, and a little above the upper one; the distal margin of each rises slightly at the caudal end, from there running first nearly straight and then toward the anterior end curving a httle downward. The fine fibrillae 294 THE ANNELIDA POLYCHAETA. extend a moderate distance distad. (Plate 45, fig. 3). The compound crochets of the first three parapodia are long and coarse. The distal segment in these is comparatively rather long and distally moderately attenuated bidentate; the superior tooth long, curved forward, narrowly rounded at tip; the inferior tooth small, acute, and straight; no distinct jutting angle or shoulder proximad of teeth; the membranous guard rising high above the level of the superior tooth, slenderly attenuated distad and very acutely pointed. The joint very distinct and the distal piece usually bent at a considerable angle with the proximal. (Plate 45, fig. 4). On the fourth to the ninth parapodia, inclusive, the com- pound crochets are replaced by simple, stout setae which distally are narrowed to a fine tip, near the base of which the setae are usually bent. (Plate 45, fig. 6). The maxillae are very thin and semitransparent, pigmented only narrowly along some of the edges, where the pigment is black. The carrier of maxillae I is short and rather broad; it is widest anteriorly, narrowed from in front of the middle, the caudal portion being subtriangular, with the caudally directed apex acutely incised; on each half of the corner there is the usual more elevated triangular area, the caudally directed apex of which hes against that of the opposite one on the median fine in front of the caudal incision. The blade narrows evenly and continuously from near the middle distad, the distal half being slender, only sHghtly curved, continuing evenly the curvature of the proximal portion. Maxilla II of the right side has eleven, mostly somewhat recurved teeth; the inner plate of the left side has eleven teeth, the outer one seven or eight. The right plate of maxillae III is strongly curved and bears a series of ten slenderly acute teeth; the left plate is but sUghtly cm'ved and bears a series of only six or seven teeth. Each maxilla IV, lying just ectad of the corresponding maxillae III, bears a single acute, dark tooth. (Plate 45, fig. 2). The mandibles are unusually small and are wholly covered. Each masticatory plate diverges from the opposite one in a cephaloectal direction; it is rather slender and distally pointed, with the anterior margin smooth, excepting for a single acute incision nearer the caudal end. The blades are but slightly attached anteriorly; they are very slender. Locality. Off Panama: Sta. 3392 (lat. 7° 06' 30" N., long. 79° 40' W.). Depth 1,270 fms. Bottom hard. Bottom temp. 36.4° F. A number of tubes containing the animals in situ were dredged 10 March, 1891. This species is characterized by its small size, short median tentacle, bi- dentate, compound, hooded crochets on the anterior parapodia, and especially by the structm-e and arrangement of the branchiae, these being all simple and ONUPHIS CRASSISETOSA. 295 present on parapodia from the sixth to the fifty third inclusive, a large propor- tion of the somites thus lacking them. Its position with reference to the other Pacific forms having all branchiae simple is shown in the following: Key. a. Anterior hooded crochets distinctly dentate and usually distinctly compound. b. Anterior crochets tridentate. c. Branchiae beginning on the first parapodia. d. Eyes present; inner left plate of maxillae II with five teeth, outer with six. e. Right maxilla III with ten teeth; upper tooth of compound crochets short, the median tooth extending outward beyond it, the lowermost tooth blunt. .0. elegans (Johnson). ee. Right maxilla III with seven teeth; upper tooth or fang of compound crochets very long, projecting widely outward beyond the others, the lowermost tooth slender and acute. 0. holobninchiata Marenzeller. dd. Eyes absent; inner left plate of maxillae II with eight or nine teeth, the outer with seven (upper tooth of compound crochets long, projecting beyond the others). O. iridescens Johnson. ce. Branchiae beginning on the third or on more caudal parapodia. d. Branchiae beginning on the tliird or foMth parapodia and continuing nearly to end of body; fang of compound crochets short, not rounded, not projecting outward beyond the lower ones O. -pallida (Moore). dd. Branchiae beginning normally on the fifth parapodia and absent from at least the last forty-four somites; fang of compound crochets much larger and proportionately more slender, distally rounded, projecting beyond the other teeth. .0. geophiliformis (Moore). bb. Anterior crochets bidentate. c. Branchiae beginning cephalad of the tenth parapodia; first parapodia not extending far for- ward, not or scarcely surpassing the peristomium. d. Branchiae beginning on the sixth parapodia, and ceasing at or near the fifty third pair; median tentacle shorter than the posterior paired ones O. lepta, sp. nov. dd. Branchiae beginning on the eighth parapodia and continuing nearly to the caudal end of the body; median tentacle longer than the paired ones. . . .0. macrobranchiata (Mcintosh). cc. Branchiae beginning caudad of the tenth parapodia; first parapodia curved strongly forward, equalling or surpassing the prostomium. d. Branchiae beginning on the seventeenth parapodia. .. .0. pycnohranckiata (Mcintosh). dd. Branchiae beginning on the twelfth to fourteenth parapodia. e. Branchiae beginning on the twelfth or thirteenth parapodia; somite II between two and three times as long as I; crochets of anterior parapodia simple; diameter near 4.8 mm. 0. hiatidenlaia Moore. ee. Branchiae beginning on the fourteenth parapodia; somite II five times as long as I; crochets of anterior parapodia distinctly composite; diameter 2 mm. O. crassiselosa, sp. nov. aa. Anterior ventral setae or hooded crochets not dentate, or but vaguely so; simple. Branchiae beginning on thirteenth parapodia O. conchylega Sars. OnUPHIS CRASSISETOSA, sp. nov.^ Plate 42, fig. 1-6; Plate 43, fig. 1-87. The general color is dark yellow. On the ventral surface over the caudal half of each specimen is a median longitudinal series of paler, whitish spots. 1 crassus, coarse, and setosa, with bristles. 296 THE ANNELIDA POLYC'HAETA. The parapodia are paler and the cu-ri and ventral glandular areas typically white. The species is represented by two incomplete specimens, each consisting of the anterior portion of the body. One of these is 23 mm. long, with a maximum width of 2 mm., and is composed of thirty-six somites. The other, which is but sUghtly shorter, consists of thirty-nine somites. The prostomium is small, proximally subcylindrical, and distally convexly or hemispherically rounded, with the ventral surface more flattened. In anterior view the tentacles are seen to be arranged in a circle. The frontal tentacles are rather small, short, and stout, distally rounded, pale colored processes attached very close together but not quite contiguous. They are much smaller than the palpi. The latter are bluntly conical, well rounded, proximally stout bodies which are very close together and project ventrad from the under surface of the prostomium. The dorsal tentacles have the usual general structure, consisting of a distinct, stout, strongly annulated ceratophore and a long, smooth, distally tapering style ; the ceratophores in comparison with those of other species are short. The anterior paired tentacles are short, reaching upon the second somite; the style is nearly three times as long as the ceratophore; the cerato- phore consists of two short proximal articles and a smooth distal region equalling about half the total length. The outer posterior paired tentacle intact reaches at present to somite IX, but the tip is broken ofT and it may have reached at least as far as XI, but judging from its slendemess at the broken end probably not as far as the median tentacle; the ceratophore appears as thick as long and consists of three annuli, of which the most distal is longest. The median tentacle reaches to somite XIII; it is stouter throughout and longer than the posterior laterals; the ceratophore is decidedly stouter than those of the laterals, but it is proportionately short, as thick as long, and consists of four annuli (or of three, the division between the two distal annuli being rather obscure). (Plate 42, fig. 1). The peristomium is abruptly much wider than the prostomium, but it is very short, "in the middorsal region being only about a third as long as the prostomium. Its anterior margin above is straight or but slightly curved at the middle. Laterally it bulges forward convexly to embrace the prostomium. The entire ventral surface is set ofT and elevated as the lower lip ; this is wholly smooth; its anterior margin is straight, or nearly so, but one specimen shows a small V-shaped incision at the middle line. The tentacular cirri are attached widely apart; each is slender and tapered to a point, and reaches beyond the base of the corresponding posterior tentacle, but does not wholly attain the anterior end of the prostomium. (Plate 42, fig. 1). ONUPHIS CRASSISETOSA. 297 The first three metastomial somites form a region strongly set off from the remaining part of the body by reason of the greater length and the greater height and convexity of these three somites ; they also differ in ha\'ing the para- podia attached at the anterior end and in having them bent more strongly forwards, and they are less sharply separated from each other than are the succeeding ones. The first metastomial somite is five times as long as the peri- stomiimi, and across its wider anterior end is not fully twice as wide as long {dr. 8 :5) . The second metastomial has the same length and breadth but appears to be more narrowed caudad. The thu'd metastomial is much shorter (aV. 25:17) and is also narrower. The fom-th is abruptly much shorter than the third (10:17) and is in the type 3.6-3.8 times wdder than long. The succeeding somites increase gradually in width to the tenth or twelfth metastomial and in the type retain nearly the same proportions, but in the paratype are longer after the first five, somites X-XII, etc., being about three times wider than long. The first parapodia are bent directly forwards along the sides of the peri- stomium and nearly attain the front margin of the prostomium, which its post- setal process exceeds ; the proximal end is thick, conically narrowing to the more slender and cyhndrical main portion ; the notocirrus is attached near the middle of the dorsal surface, is constricted at base, and as a whole slender and pointed; the neurocirrus is attached on the opposite surface, btit at the base it is similar in form and equal in size, or nearly so, to the notocirrus. The distal end of the parapodium presents a prominent, cirrus-like, postsetal process which tapers to a point from a moderately wide base and has its tip nearly on a level with that of the notocirrus where both extend directly distad. (Plate 43, fig. 3). The second parapodia are much shorter than the first and are du-ected ecto- cephalad and somewhat ventrad instead of directly cephalad; the cirri and postsetal finger are of essentially the same length and form as in the first. (Plate 43, fig. 4). The third parapodia are again shorter than the second and are directed more ectad; the notocirrus remains equally long and of the same form, and the postsetal process is but little reduced; on the contrary, the neiu"ocirrus has a decidedly different form, appearmg as a short, stout, rounded prominence. (Plate 43, fig. 5). In the fourth (Plate 43, fig. 6) and all succeeding parapodia, the neurocirrus is evident onl}^ as the usual flattened scale merged in the ventral glandular area. The notocirrus continues well developed on all parapodia to the end of the fragments, but caudad becomes, as usual, much more slender. The postsetal process becomes gradually reduced to a low, pointed process, and 298 THE ANNELIDA POLYCHAETA. finally disappears at about the sixteenth parapodia. The parapodia from the fourth on are attached near the middle of length of somite and are shifted farther dorsad, as usual. All branchia are simple unbranched filaments which are mostly more or less flattened. The first branchiae detected are on the fourteenth parapodia in both specimens ; they are shorter than the notocu-ri, are a little tapered distad, but with the distal end not acutely pointed. Branchiae of similar form continue to be present on all the following parapodia to the end. They may become, in some cases, a little longer than the cirri, but in no case exceed half the dis- tance to the middorsal hne, usually falling distinctly short of half the distance. (Plate 43, fig. 7). The ventral acicula are moderately stout structures, the exposed distal portion of which terminate in a fine, short, curving tip. (Plate 42, fig. 6). The setae of the dorsal group are long. For most of their length they are straight and capillary, but toward the distal end each is bent. On each side in the region of the bend broadened by two distinct Umbi or wings and distally narrowed to a long fine tip. (Plate 42, fig. 5). There is a ventral group of similar hmbate setae on all but the anterior parapodia. The ordinary crochets, two in num- ber in each parapodium, are long and much exposed, and of uniform width over most of their length; at the distal end bidentate, both teeth bent out at right angles to the general axis and the distal one the smaller; membranous guard shghtly exceeding the teeth, the distal edge straight and rising obliquely from near the lower tooth to above the upper one; strongly fibrillate distad to the cervix. (Plate 43, fig. 2). The pectinate setae are short, deUcate, and trans- parent ; the expanded distal end is rolled in the form of a hollow cone, with a sector of about one third missing. The distal margin fringed and the ends each angularly extended mesad into a characteristic triangular flap. (Plate 43, fig. 1). The crochets of the first parapodia are of about the same proportions as those of the other regions of the body, but they present a strong joint and the teeth are of different shape and proportions, the distal one being much the larger, the subapical one much reduced; the joint is very obhque and situated well distad. (Plate 42, fig. 4). On the fourth foot the compound crochets have been replaced by simple ones, one to each parapodium, in which the teeth are of somewhat intermediate character. The dorsal setae in the anterior parapodia are strongly limbate and bent, as elsewhere, but are apparently shorter. The maxillae are thin and translucent, darkened along some of the edges ONITHIS CRASSISETOSA. 299 and over the distal part of the fang of maxilla I. Maxillae I with the carrier- plate equal in length and breadth; on each side incurved at the anterior end and then convexly rounded caudad as usual; each half obliquely bent so as to leave an anterior triangular area more elevated. The blade is short, broad proximally, and rather abruptly narrowed at the middle to the fang, which is neither long nor strongly curved. Right maxilla II with nine stout, blackish teeth, of which the most anterior is decidedly largest ; the left outer plate with seven teeth, of which the anterior one is enormous in comparison with the others, appearing somewhat like the blade of maxilla I laut proportionately much broader ; the inner plate has eight teeth which are stout and darkened, regular, the most anterior not being larger than usual. The right maxilla III is a long, strongly curved plate bearing twelve teeth; the right plate is considerably shorter but is also strongly bent and bears ten teeth. Each maxilla IV is darkened and ele- vated in a somewhat dentiform process at its anteromesal angle. (Plate 42, fig. 3). The mandibles are well developed, with the masticatory plates visible when in situ. These plates are large, hard, white, and strongly diverging, the anterior margin of each incised and dentate near its middle. The stems are narrowed caudad and are scarcely united anteriorly; they are conspicuously darkened. (Plate 42, fig. 2). Localities. Off Central America: Sta. 4621 (lat. 6° 36' N., long. 81° 45' W.). Depth 581 fms. Bottom of green sand. Bottom temp. 40.5° F. 21 Octo- ber, 1904. Two specimens in tubes. Off Galapagos Islands: Sta. 3401 (lat. 0° 59' 0" S., long. 88° 58' 30" W.). Depth 395 fms. Bottom globigerina ooze. Bottom temp. 43.8° F. One incomplete specimen with hyahne tube attached to siUcious sponge rod as in those from the preceding station, 28 March, 1891. From most other Pacific forms with simple branchiae and the anterior crochets only bidentate, this species is most easily distinguished in having the branchiae begin on the fourteenth parapodia, instead of the sixth in lepta, eighth in macrobranchiata, seventeenth in pycnobranchiata, and twelfth or thirteenth in hiatidentata. In the case of hiatidentata the relationship is undoubtedly very close, as shown in structure throughout; but nmnerous differences in details render the separation of the two forms necessary, especially in view of the fact that specimens of the present species from two well-separated stations show con- stancy in these differences. The present species is very much smaller, having a maximimi diameter of only 2 mm., instead of 4.8 mm. in hiatidentata. At the same time the dorsum in general is less strongly arched, and is narrowed at the 300 THE ANNELIDA POLYCHAETA. anterior end in the more usual way instead of being specially stout. The palpi are shorter and not at all bilobed. The lower lip is not bilobate. The peri- stomium is much shorter in comparison with somite II. The somites in general are distinctly longer in proportion, somite V being only from three to three and four fifths times wider than long as against six times wider in hiatidentata. The branchiae begin on the fourteenth parapodia instead of on the thirteenth (or twelfth), and the first ones are shorter than the notocirri instead of equalling them. The crochets of the anterior parapodia are conspicuously different so far as Moore's account of hiatidentata shows, for they are distinctly compound and the superior tooth is much more elongate. Two crochets appear in each para- podium beginning with X in this species, but not until XV in hiatidentata. The pectinate setae differ in the presence of the conspicuous angular flaps at the distal corners. Onuphis cobra, sp. nov.^ Plate 52, fig. 1-8. The general color is a dark dusky brown, with the appendages somewhat paler. On the ventral surface the glandular areas along each side are pale, as usual, as are also a number of infraganghonic spots along the midventral line. None of the type-specimens is wholly complete, though both anterior and posterior ends are present. In the two fragments representing the paratype there are thirty-one (anterior) and thirty-nine (posterior) somites respectively, the two fragments in length measuring respectively 27 and 21 imn. The great- est width, exclusive of the parapodia, is 4 mm. The prostomium is broad and well exposed, the tentacles being all distinctly removed from the edge of the peristomium. Anteriorly it bears the two cushion- like palpi, which are longest dorsoventrally, thickest at the ventral end, and well separated from each other. The frontal tentacles are very low and rounded, inconspicuous, and scarcely separated at the middle. Between the furrow separating off the frontal tentacles above and the bases of the dorsal tentacles the prostomium is somewhat complanate. The dorsal tentacles are arranged somewhat in a semicircle, the median being farther caudad, from this each posterior lateral being well separated by about the diameter of the ceratophore. Each anterior lateral tentacle is inserted much nearer to the posterior lateral than the latter is from the median, and is but little ectad or directly cephalad of it, being attached at the cephaloectal border of the peristomium. The cera- ' Portuguese for Cobra de eapello. ONUPHIS COBRA. 301 tophorcs are distinct and but rather weakly annulate, three or four annuli being present. The styles are as thick at base as the ceratophores and gradually taper to the distal end; they are wholly smooth and unjointed. Each tentacle of the anterior pair reaches the second somite. Each of the posterior paired tentacles reaches the tenth somite, or near that, the exact point being in doubt because of the difficulty of uncoiling the style. The ceratophore of the median tentacle is longer and stouter than those of the laterals; the style reaches the twelfth or thirteenth somite. The peristomium is short, being but little more than half the length of the prostomium, and only about a third as long as the second somite. The anterior margin above is nearly straight. On each side it curves moderately broadly forwards and is shghtly notched at a point from which a wide furrow extends caudad. The lower lip is triangular, with the apex caudad, and is much wider than high; it is set off on each side by a deep furrow extending from the anterior border on each side caudomesad; the anterior margin is nearly straight, with a slight notch at the middle, from which a weak median longitudinal furrow extends to the caudal end. The surface above is smooth. The tentacular cirri are attached caudad of the anterior margin but in front of middle of length, each in line with the corresponding posterior paired tentacle ; each cirrus is verj^ slender and tapered and is long, extending beyond the attachment of the other cirri, or forward to a little beyond the anterior margin of the prostomium. The first metastomial somite is wider and much longer {cir. three times) than the peristomium and is, as usual, widest across the anterior end, where it is a little less than two and a half times as wide as long. The second metastomial somite is about tliree foiu-ths as long as the first, and is three times wider than long. The third is somewhat shorter than the second, while the fourth and suc- ceeding ones are abruptly decidedly shorter than the third, the first three meta- stomials and the prostomium being set off more or less as a distinct region of the body. The somites increase in width to the tenth or twelfth, in which the width is almost five times the length. The succeeding few somites decrease rather rapidly in width, and thereafter the body remains nearly of uniform width to the caudal region, in which a more rapid decrease again occurs. Dorsally the somites are well arched and ventrally flattened. The anus is distinctly dorsal in position ; it is surrounded with a broad elevated rim crossed by numerous deep radial furrows. Below the anus are attached two long, smooth, and slender anal cirri which, when drawn forward, reach almost to the tenth or twelfth somite from the anal end. 302 THE ANNELIDA POLYCHAETA. The first parapodia occupy the usual position at the anterior border of the second somite, from which they extend forward a httle ectad of cephalad along the sides of the peristomium, which they surpass, though, excepting the processes, falUng decidedly short of reaching the anterior margin of the prostomium. They are very deep dorsoventrally, being somewhat compressed transversely. The notocirrus is a tapered process of the ordinary form attached on the dorsal surface near the middle of the length and extending distad nearly to the anterior margin of the prostomium. The neurocirrus is attached at the base on the ventral side; it is swollen proxunally, above this narrowing rapidly to a more slender process ; it appears in the type to fall short of reaching the distal end of the foot. The postsetal process appears to have been worn off, but was appar- ently broad and distally rather blunt. The second parapodia are similarly attached to the first, but they are much shorter and extend more ectad of cephalad. The notocirrus is attached nearer the base; it is a conspicuously tapered and long process extending about two thirds the distance to the middorsal hne. The neurocirrus is short, strongly swollen at base, and conical in form. The third parapodia extend in a still more ectal direction and are attached near the middle of somite; like the second they are cyUndrical, and distally subconically narrowed and rounded. The notocirrus is Uke that of the second pair. The neurocirrus is in the form of a swollen, rounded cushion. The postsetal process is apparently broken off in both specimens. The fourth parapodia extend almost directly ectad, and are attached at the middle of the somite and farther dorsad than the first three pairs, which are near the ventral level ; the parapodium as a whole narrows distad from the base and is well rounded at the end. The notocirrus is similar to the preceding ones, but is a little longer. The neurocirrus has become disc-like and merged in the ventral glandular area. The postsetal process is a conspicuously elongate, cirrus-Uke finger tapering to the free end. The fifth parapodia are attached near the dorsal level. Their general structure is like that of the fom"th. Succeeding parapodia maintain the same general structiue. But the notocirri become much more slender, in the posterior region being long and almost thread-like. The postsetal process continues to be evident on many parapodia, but at the twenty second has become reduced to a much shorter, pointed process; the precise point at which it ceases to be evident co\ild not be determined. The setae in general are light brown, or somewhat ferruginous in color, are coarse, long, and over much of the body overlap those of each succeeding somite. On the first parapodia there are tliree long, stout, distally conspicu- ONUPHIS COBRA. 303 ously curved setae. These are, apparently, unjointed hooded crochets of the bidentate type. The apical tooth is long, stout, and distally curved caudad; the subapical tooth is very small and extends directly caudad. (Plate 52, fig. 8). On the second parapodia long capillary setae of the type occurring on the more typical parapodia make their appearance. The ordinary crochets first occur singly, on the eighth somite in the paratype and at least as early as the tenth in the type and probably similarly on the eighth. Farther caudad two crochets appear in place of the one, the first somite on which the two were noted being the nineteenth, though they may occur earUer, the rubbed condition of the speci- mens preventing entire certainty. (Plate 52, fig. 7). The acicula have the usual general form. Just after its emergence each is abruptly reduced to a fine, acute tip. The medulla is strongly fibrillate distad to the exposed pale portion. (Plate 52, fig. 4). The form of limbate setae is shown (Plate 52, fig. 5) and that of the delicate pectinate setae in figure 6 of the same plate . In a typical parapodium of the middle or posterior region, each of the two crochets are very long and of uniform diameter nearly to the region of the con- stricted cervix, just below which it is curved, being elsewhere straight. Distally it is bidentate, the teeth being long and acute; the subapical tooth is stouter than the apical, and lacks an abrupt bend evident in the latter. The membran- ous guards rise well above the level of the apical tooth and narrow to a point distally. The medulla is strongly fibriUate distad as far as the cervix, and a few short separate fibrillae are evident in the base of each tooth. The dorsal and ventral limbate setae are similar in structure. Each presents a long, straight, strictly capillary shaft and a short, abruptly bent, or geniculate, distal portion which is bihmbate and attenuated to a fine acute tip ; the medulla is very finely fibriUate and the \\ings are obUquely striate, as usual. The pectinate setae are rather numerous, forming a conspicuous dorsal fascicle. They are delicate and transparent, and usually average about half the length of the exposed part of a crochet. The distal expanded portion flares rather strongly, the distoectal corner being prolonged and often curved back mesad. The teeth along the free margin are short and uniform. The branchiae occur first on somite XV, each as a simple fUament which is very short, its length being more than once but less than twice the proximal diameter of the dorsal cirms. All the remaining branchiae are also simple and cirrus-like, distinctly flattened. The second branchiae are broader than the first and fully twice as long, equalUng half the length of the notocirrus, from the base of which it springs, and also exceeding the greatest diameter of the latter. 304 THE ANNELIDA. POL YCHAETA. The succeeding branchiae continue of this form and of nearly the same pro- portions, in no observed case exceeding two thirds the length of the cirrus, in the posterior region decreasing in length and finally becoming almost rudi- mentary, but continuing to be present very nearly to the last somite. The maxillae are well chitinized and are in large part dusky. The carriers of maxillae I have a characteristic form, together forming a plate widest across its anterior end and narrowing caudad in subtriangular form, but with a deep median incision from the caudal end; each lateral margin is gently incurved at the middle of its length; an elongate triangular area on the mesocephalic portion of each piece is more elevated and is paler in color. Each blade is nar- rowed a little in front of the caudal end, then widens again before more strongly narrowing to the slender, gently curved, distal division, or fang. The right piece of the maxiUae II bears nine teeth of nearly uniform size, but with the proximal ones broader and more obtuse. The inner plate on the left side has ten teeth, of which the ones at the caudal end of the series are lower and more rounded, appearing like crenations, the most distal tooth not enlarged. The outer left plate of the second maxillae bears also ten teeth which, beginning at the caudal end as low, small crenulations, increase gradually distad; the most distal tooth is much larger than the others and is separated by a wide space. The right maxilla III bears eleven teeth in a well-curved series, the caudal one being low and blunt, and those at the ectodistal end longer and acute; the left plate has nine teeth also in a well-curved series. Each maxilla IV is a sub- quadrate plate on which the distomesal angle is darkened and somewhat reflexed. (Plate 52, fig. 3). In the mandibles of the types the masticatory plates are all broken; they are hard, white, and foliate, but the exact form cannot be made out. The stems are expanded at the anterior ends as supports for the masti- catory plates, from where they narrow caudad ; they are long, curve outwards near their middle, and then mesad at the caudal end where they approach each other; they are darkened caudad to about the middle of theu- length, the poste- rior half being whitish. (Plate 52, fig. 2). Neither of the type-specimens is complete, one being represented by two fragments, the other by three, anterior and caudal ends being present in both cases. In the two fragments representing the paratype there are thirty-one (anterior) and thirty-nine (posterior) segments respectively, the fragments in length measuring respectively 27 nmi. and 21 mm. The greatest width, exclusive of the parapodia, is 4 mm. The general color is a dark, dusky brown, the appendages being somewhat ONUPHIS COBRA. 305 paler. On the ventral surface the glandular areas along each side are paler, as usual, as are also a number of infraganglionic spots along the midventral line. The tubes consist of a thin lining membrane with a thick coat of fine, dark greenish grey mud, in which are numerous Globigerina shells, etc. The longest tube, apparently incomplete, is 22 mm. long and has a maximum external diame- ter of 8 mm. The smallest tube has a diameter of 5 mm. One tube has attached to it a piece of decaying wood. Locality. Off Panama: Sta. 3381 (lat. 4° 56' N., long. 80° 52' 30" W.). Depth 1,772 fms. Bottom of green mud. Bottom temp. 35.8° F. 6 March, 1891. Two specimens and several tubes. This species is close in its general structure to hiatidentata Moore and to crassisetosa, sp. nov. From both these species it differs in form and proportions and in having the branchiae much shorter, these being always much exceeded by the notocirri, which are unusually large, as if in compensation for the shorter cirri, as well as in having the branchiae all conspicuously flattened. From hiatidentata it differs in ha\'ing the branchiae begin on the fourteenth parapodia instead of on the thirteenth; decidedly in the triangular form of the carrier of maxillae I, and in the number and form of the teeth of the other maxillae. The ceratophores of the tentacles are proportionately more slender. From crassisetosa it differs in being decidedly larger, the diameter being 4 mm. as against 2 nam., and in presenting a conspicuously widened region back of the narrow anterior end. The first metastomial somite is decidedly shorter in comparison with the peristomium. In the maxillae the carrier of I differs in being strongly narrowed caudad; the distal tooth of the outer left plate of II is proportionately much smaller, and its teeth number ten instead of but seven, the inner plate being also ten as against eight, while the right plate has eleven as against nine, the teeth differing in form as well. The pectinate setae resemble those of crassisetosa in ha\dng the reflexed angles at the distal end, but these are smaller and less conspicuous. The setae of the first parapodia differ in being apparently un- join+ed. The tube of the present species is of mud over a thin lining membrane, whereas in crassisetosa the tube is simply hyaline without foreign adherent material. 306 THE ANNELIDA POLYCHAETA. Pakontjphis Ehlers. Mem. M. C. Z., 1887, 15, p. 67, 73, 78. Paronuphis solenotecton, sp. nov.^ Plate 39, fig. 3-8; Plate 40, fig. 1, 2. This species, so far as indicated by the type-specimens, is decidedly smaller than most species of Diopatra, the maximum length noted being only about 30 mm. The maximum width, exclusive of the parapodia, is 2 mm., and in- clusive of the parapocUa, 2.25 mm. An incomplete specimen, the length of which cannot be judged, has a maximum width, exclusive of parapodia, of 2.4 mm. No specimen removed from the tube was whoUy complete, the thinness of the walls of the posterior somites resulting in easy breaking and disintegration. The number of somites is hmited, as nearly as can be judged, being only about forty. Body widest at from the twelfth to the sixteenth somite, from where it narrows conspicuously cephalad and conspicuously, but more gradually, to the caudal region, whence of uniform width to the pygidium, which narrows abruptly to an acute point. The general color is brown. A pale ventral and dorsal median longitudinal line, of which the dorsal is less distinct and over much of the length may be scarcely or not at all evident ; both hues with a tendency to break into separated dots. Parapodia also hghter colored, yellowish. Setae very pale. Prostomium as viewed from above broadly subtriangular, but with the sides and the apex rounded, the whole sometimes appearing somewhat semicircular. A transverse furrow or constriction, in line with the anterior edges of the anterior lateral tentacles, separates off a subtriangular apical division. There is a trans- verse furrow caudad of the unpaired tentacle, behind which the prostomium is more elevated as a transverse ring, which is very short mesally. There is also a semicircular furrow just in front of the median tentacle, with its convexity forward. The frontal tentacles are attached on the front margin toward the ventral side, extending cephaloventrad and at the same time diverging strongly from each other. They are short and stout, being mostly only half, or less than half, the length of the prostomium; in outhne, elliptic to broadly subconical, with tip rounded. Either slightly removed from each other at base or in actual contact. The anterior paired tentacles are attached a little caudad and ectad ' au\(p, tube, and t(kto}p, artificer. PARONUPHIS SOLENOTECTON. 307 of the frontal tentacles on the lateral edge of the prostomium, a little higher than the frontals. They are short, reaching only upon the first parapodiferous somite or to the beginning of the second. Ceratophores about equalhng the frontal tentacles in length but more slender, obscurely four-ringed, or nearly smooth; style smooth, gently tapering, tip not fine. Posterior paired tentacles on each side situated a little above lateral edge of prostomium, immediately back of paired tentacle and in contact, or nearly in contact with it. Cerato- phore of essentially the same size as those of anterior pair, smooth, or but very obscurely few ringed; style slender, subulate, smooth, reaching to or beyond somite V, its tip in all types examined being broken off. The median tentacle is located caudad of the middle line; its ceratophore is much longer and stouter than those of the pau-ed tentacles; it is similarly nearly smooth, a few annuli being but vaguely indicated ; style correspondingly stouter and longer than that of the paired tentacles, reaching to and probably a little beyond somite IX, its extreme tip in all types being broken off. The palpi are thick, fleshy, hemispheri- cal lobes on the ventral side of the anterior portion of prostomium. No eyes detected. Peristomium very short, being but slightly or not at all more than half as long as the prostomium, conspicuously wider anteriorly than the prostomium, the posterior sides of which it embraces; dorsum strongly convex; anterior margin mesally gently convex. The cm-i are attached on the anterior margin widely apart; each is pale in color, regularly tapered to tip, and short, clearly shorter than the distance to base of opposite cirrus and also shorter than the prostomium. The lower lip is a large, smooth, and uncUvided transverse fold. The next succeeding somite (II) is much longer than the peristomium, being about three times the length of the latter; it widens cephalad, extending out somewhat at the sides to bear the long parapodia. Somite III of the same general form as II, flaring cephalad, but clearly shorter. Somite IV is still shorter, and V is intermediate between IV and the inmiediately succeeding short somites, which do not differ much in length among themselves. Beginning with about somite XIII the somites again increase conspicuously in length, in the middle and posterior regions bemg nearly or quite half as long as wide. Pygidium very small, subtriangular in outlme. Anus a subdorsal sUt, the sur- face through which it opens obhque. The first parapodia extend forwards and a httle ectoventrad; they are conspicuously long, their anterior ends being about on a level with the anterior tip of the prostomium; proximaUy thickest, swollen and high above, narrowing 308 THE ANNELIDA POLYCHAETA. distad abruptly beyond the notocirrus to the subcircularly rounded, flattened, presetal hp; the postsetal process rounded at the end and attached farther proximad, and ahnost reaching distad to the tip of the postsetal Up ; the ventral cirrus is attached at base of parapodium; it is a tapering piece of nearly same form and size as the postsetal process or median cirrus ; notocirrus more slender than median cirrus, tapermg, not reaching to end of postsetal lip. (Plate 39, fig. 4). The second parapodia are in general similar to the first ones, but are shorter and are directed more ectad; the terminal button or postsetal lip is smaller; the neurocirrus is decidedly more swollen proximally; the notocirrus is longer and, conspicuously beyond the postsetal hp, or tip. (Plate 39, fig. 5). The third parapodia are abruptly much shorter than the preceding; the presetal lobe is further reduced and is less rounded, distally pointed; the postsetal process, or median cirrus, much exceeds the end of the parapodium ; the ventral cirrus is a much thicker, subconical, distally rounded process; the notocirrus much exceeds the tip of the presetal process, but is shorter absolutely, though not relatively, than that of the preceding pair. The fom-th pair are much shorter than the third and extend almost directly ectad, their direction making a con- spicuous angle with that of the preceding ones; the presetal lobe is further reduced and relatively narrower; the neurocirrus appears as a conspicuous subglobular tubercle, a character mamtained on the following parapodia. The succeeding parapodia become gradually shorter and finally appear simply as rounded eminences on which the presetal and postsetal processes have become reduced to mere points, or quite obUterated. Caudad from the fourth para- podia the length of the notocirri for a while remains nearly constant ; they then undergo a marked reduction in size and finally disappear at or near the thirty second somite. Setae of first parapodia few, long, stout; compound, the oblique articulation distinct; setae conspicuously curving near level of and especially above the articulation; terminal tooth short, conspicuously curved; the accessory tooth short, straight, widely separated from the apical one; guards well developed, distally rounded, somewhat obhquely prolonged. (Plate 39, fig. 8). Acicula of first parapodia slenderly acutely pointed, the tips not much protruding. On the second parapodia there appears a conspicuous fascicle of usually numerous, fine, transparent pectinate setae in a dorsal group, each with the usual slender stalk and clavately expanded, curved end piece with the series of teeth along distal border; these pectinate setae occm- also on the succeeding parapodia, as usual. (Plate 40, fig. 1). On the second parapodia also appear simple setae PARONUPHIS SOLENOTECTON. 309 which are finely pointed, very narrowly limbate, and distally curved. The stouter compound setae occui- in a ventral group on the second and also the third parapodia. On the succeeding parapodia the limbate setae become longer and more numerous, with broader limbus, and are arranged in a dorsal and a ventral group, the dorsal being longer than the ventral, and the pectinate setae occurring in conjunction with them. (Plate 39, fig. 7). The stouter, hooked posterior setae occur first on the tenth, eleventh, or twelfth parapodia, one or two on the first on which appearing, and two on each succeeding parapodium. These setae are stout and straight excepting for a weak curvature toward the distal end; the teeth stout, acute, the distal one strongly curved, the lower one straight, oblique, making an acute angle with the first; guards conspicuously developed, transparent, striate, distally ending in a subacute point. (Plate 40, fig. 2). Maxillae pale excepting more especially the tips of the forceps, across their proximal ends and edges of the supports, which are black. Maxillae I with supports relatively long, each half acutely pointed at caudal end with caudal notch between the two halves, anterorectal angle obliquely truncate, and the caudoectal angle with a much longer obhque truncation, the side between the two oblique faces straight or nearly so; forceps proper tapering distad, the tip slender, bent strongly mesad, the broader proxunal end with a laminate extension on mesal side extending to about middle of length. (Plate 39, fig. 6). Maxillae II with right plate, in the specimen dissected, with nine black-tipped teeth which at caudal end are small and close, but cephalad with the spaces larger and conspicuously wide, each tooth long, acute, and somewhat distally curved; the most anterior longer and more strongly hooked; the left inner plate with eight or nine similar teeth, the outer plate with same number, but with the most anterior tooth especially long, and with a much wider space be- tween the succeeding tooth and the third one than between others; a laminate extension opposite this wider interval; the plates anteriorly are bent ectad, as usual. Maxillae III are exceptionally long; the plates from the caudal ends cephalad are convex, with the anterior ends more strongly curved and extending ectad; left plate with ten teeth, right with twelve or thuteen. Maxillae IV with a single black-tipped tooth at comer of mesal end, the plate narrowing ectad and curved somewhat caudad. The mandibles with masticatory plates large and white, each extending cephaloectad and diverging from the other in the usual way; tip prolonged and subacute or often worn and rounded, a notch proximally on ectal side, and a very conspicuous excision on the mesal side, with a well-marked ventral fmrow extending caudad from the excision; stem below 310 THE ANNELIDA POLYCHAETA. the expanded portion bearing the masticatory plate slender, nearly uniform in width anteriorly, the caudal ends of the two bending mesad toward each other, the mesal edge of each bulging mesad near middle of length; the two stems firmly united just caudad of the masticatory plates. (Plate 39, fig. 5). Numerous tubes are represented in the collection. These are all con- spicuously flattened, and are moderately narrowed toward one end. A typical tube is about 40 mm. long and 5 mm. wide at the larger end, the lesser diameter being but 2 mm., or scarcely more. There is the usual thin, but moderately tough, lining membrane densely encrusted with the shells and shell-fragments of vari- ous Foraminifera. Of these shells the large discs of Spirillina are especially conspicuous, occur on all the tubes, and range in diameter from 4 nun. down. In addition, shells of Globigerina are abundant, as are also those of Nodosaria. The elongate shells are nearly always arranged either strictly transversely or somewhat obliquely. Locality. Off Panama: Sta. 3392 (lat. 7° 05' 30" N., long. 79° 40' W.). Depth 1,270 fms. Bottom temp. 36.4° F. Bottom hard. Numerous tubes containing animals. 10 March, 1891. This form is characterized particularly by the large maxillae III with their large number of teeth (ten to thu-teen) , exceeding the number on maxillae II (eight to nine) , and the presence of pectinate setae in abundance as far forward as the second parapodia, as well as by the detailed structure of the setae, form of the cirri, and other details. The tube in being strongly flattened differs con- spicuously from those of Paradiopatra fragosa and P. glutinatrix described by Ehlers (Mem. M. C. Z., 1887, 15, p, 75, 76) from off Florida and made the basis of Paradiopatra, the tubes in these two latter species being cylindrical. Hyalinoecia Malmgren. Annulata Polychaeta 1867, p. 67. Hyalinoecia tecton, sp. nov.^ Plate 38, fig. 4-9; Plate 39, fig. 1, 2. The general color of the specimens from Sta. 3424 is light yellow, in some becoming darker in the caudal region. In the caudal region and for a vary- ing distance forward there may be .a conspicuous, geminate, discontinuous median ' rkKTi^f, ail artificer or craftsman. HYALINOECIA TECTON. 311 longitudinal dorsal stripe of dark red color. The type-specimen, from Sta. 3425, is much darker throughout ; the dorsum anteriorly is a dark brown ; but in the middle and caudal regions this darker color becomes denser and restricted to two longitudinal bands, leaving a pale band on each side and a wider median pale band embracing the geminate, interrupted, median stripe. The venter is brown anteriorly, becoming denser caudad, with a narrow pale stripe along bases of the parapodia over the glandular areas, the parapodia themselves being also paler. The body above is evenly convex, caudally becoming more depressed and with a distinct shallow and wide furrow along each side just within the para- podia, and a weaker depression along the middorsal ridge. The venter is less convex, and has a distinct median longitudinal fiu-row which deepens caudad. The body is deepest a little in front of the middle and becomes conspicuously thinner, flattened, from there toward the ends. The maximum width is attained near the middle and varies but little from there caudad except at the very end, though some specimens increase in width to near the caudal end. A specimen 68 mm. long has a maximum width, exclusive of parapodia, of about 8.2 mm. and a maximmn depth of 6.6 mm. The largest specimen from Sta. 3424 is 75 mm. long. The type is 75 mm. long, with a maximum width of about 8 mm. It is more strongly flattened caudally and less so anteriorly than above noted. Number of somites seventy-six to ninety. Prostomium somewhat trapezoidal, but with the angles rounded. Anterior margin convexly rounded and the caudal margin widely convex; the sides straight. The median and both pairs of lateral tentacles situated on the posterior half of the prostomium, the anterior laterals being attached at the edges but little cephalad or directly ectad of the posterior laterals, and with the latter and median tentacle, forming a sUghtly ciu'ved row. In this row the ceratophores decrease in thickness and length from the median to the most ectal on each side; cera- tophores rather obscurely ringed, sometimes constricted about the middle so as to give two large and equal rings, with a less evident constriction above and below this, giving two adjacent median rings which are short and two larger terminal ones, or in other cases foiu" more nearly equal annuh may be traced. Median tentacle reaching somite XV, posterior laterals XII, and the much shorter anterior laterals IV. The frontal tentacles veiy short, considerably less than half the length of the prostomium, subeUiptic in outline, more than half as thick as long, strongly divergent and directed somewhat ventrad. Palpi rounded, elevated, strongly rugose. 312 THE ANNELIDA POLYCHAETA. Peristomium well developed. Seven eighths or more the length of somite II and about two thirds as wide. Lower lip longitudinally rugose. Somite II, conspicuously larger than I and extending forwards and embrac- ing the sides of the latter, its large parapodia well forward. Subdivided dorsally by a weak transverse furrow, the caudal division the shorter. The next seven to ten somites very gradually decrease, the somites over the middle region remain- ing nearly equal, short, the ratio of length to width being only about one to ten or eleven. At the caudal end the somites become still shorter. Parapodia, excepting anterior pairs, not prominent. Parapodia of somite II, as usual, much the largest. These project obUquely ventrocephalad, extend- ing ventrad much below the general ventral surface of the body and forwards to near the level of the anterior end of the prostomium; narrowing distad, tip compressed in an oblique direction and with a conspicuous, slender, finger-like, or cirriform, postsetal process. Notocirrus near middle, this a simple style with- out differentiated cirrophore and not reaching end of parapodimn. Neuro- cirrus similar to notocirrus but shorter, attached on ventral surface proximad of the middle. The second parapodia (on somite III) are decidedly shorter and less stout than the first, but are still much larger than the following ones. They project conspicuously obliquely cephaloventrad in a direction parallel to the fu'st ones. The notocirrus is longer, passing the tip of the parapodium. The postsetal process is also longer, reaching to the distal end of the setae, in the form of a slenderly triangular, compressed process furrowed along the middle of both surfaces. The neurocirrus is proportionately longer and attains, or very nearly attains, the end of the parapodium. The third parapodia are still shorter and project more horizontally. The notocirrus is longer, exceeding the para- podia and attaining the tips of the seta. The neurocirrus is stouter and shorter, subcortical. The postsetal lip is of the same form and size. The fourth para- podia are of essentially the typical form and in the typical position. They are a little shorter and distally blunter than the preceding. In none of the para- podia is there a distinct presetal Up. The postsetal processes remain large and of nearly uniform length back to about the twelfth or fifteenth somite, and then become gradually reduced to sUght, pale papillae, in the caudal region being scarcely evident. The neurocirrus is still shorter and more bluntly rounded on the fifth parapodia, on the sixth is abruptly reduced to a slightly elevated broad papilla, and on succeeding ones is further reduced and merged in a low, glandu- lar sweUing at base of parapodia, these glandular areas becoming shorter caudad. With the appearance of the branchiae the notocirri become much HYALINOECIA TECTON. 313 reduced and project on the outer side of the bases of the branchiae only as very short subulate processes. The branchiae begin on somite XVIII, XIX, or XX either symmetrically or farther forward on one side than on the other. Thus, on one specimen they appear first on somite XVIII on the right side, and on somite XX on the left. They seem most commonly to appear first on somite XX. They increase in length gradually, and commonly reach a maximum length between somites XL and LX, where their length may equal or sUghtly exceed the width of the somite. The branchiae are flattened, but narrow and acutely pointed. Each at present shows a shallow longitudinal furrow over the large axial blood-vessel. They occur caudally on all excepting the last two or three somites. The neuropodial acicula are yellow in color. They are mostly four in number in each parapodium. They are stout, nearly straight, and acutely pointed, the tips projecting freely from the surface. The setae of the first parapodia are simple, stout, distally acuminate and entire, and are evenly and moderately curved, acicuhform. The tips of some are finely acute, those of a second, stouter type, more rounded. They may show a very fine roughening distaUy in the form of sublongitudinal lines, and some more proximally show annular impressed lines. (Plate 39, fig. 1,2). These on succeeding parapodia are replaced by sunple, much finer setae, each of which ends in a lanceolate limbate blade drawn out to an exceedingly fine tip. The setae are curved at the junction of the slender shaft and the broader blade, while the blade itself is more or less evenly curved in the opposite direction, the fine colorless tip again bending back in the other direction. The limbi are very narrow and are crossed by obUque striae, as usual. (Plate 38, fig. 9). The setae of the ventral group have the blades shorter than those of the dorsal group. (Plate 38, fig. 8). In the middle and posterior regions there appear in each fascicle two, and sometimes three, darker hooked setae or crochets. These are shorter than the limbate setae. Each is moderately curved and narrowed below the teeth. The teeth, which are protected by the usual membranous hood, are stout and subequal, each con- vex on its ectal edge and straight on its inner, or the upper one a httle concave; the two are at a moderate angle to the axis. (Plate 38, fig. 6). Associated with the setae of the dorsal fascicle is a tuft of much shorter, very fine and delicate setae, each of which ends in a clavately expanded plate bent into a half or three fourths hollow cone, like a funnel with, a sector removed. The fine distal edge is pectinate, as usual, and the surface often appears roughened with longitudinal lines and with punctae. (Plate 38, fig. 7). 314 THE ANNELIDA POLYCHAETA. Jaws rather thick, strongly chitinized. Caudal pieces of forceps-jaws, or maxillae I, very broad, the greatest width of the two together clearly exceeding the length, the ratio being about six to five. Each caudal piece or carrier is roughly subtriangular, with the apex caudad, but with the ectal side convex and even, the caudal end narrowly rounded, a median notch caudally between the two pieces. A conspicuous thickening or ridge obliquely from anteroectal corner to near middle of inner edge on each piece. Basal portion of forceps constricted a little above base and widening gently distad, widest at distal end, roughened with two curved ridges on face at proximal end. Distal division stout, rather uniformly tapered, moderately strongly curved. Maxillae II dark, blackish. Left outer plate with twelve or thirteen teeth, the inner with eleven or twelve. Right plate with thirteen or fourteen teeth. Maxillae III with nine teeth (left plate). (Plate 38, fig. 5). Maxillae IV with a single tooth. Mandibles blackish back of the '\\hite masticatoiy plates, the stems becoming pale brown to whitish. Masticatory plates large and oblique. Stems narrowest cephalad of middle, gradually enlarging caudad, at the same time incurving and in contact at the caudal end. The two halves separate. (Plate 38, fig. 4). Of about a dozen tubes, the largest is nearly 265 mm. long, and 10 mm. in diameter across the larger end in the longer direction, the lesser diameter across this end being 8 nmi. At the small end the large diameter is about 6.5 mm., the smaller 5.2 mm. The tubes much resemble those of H. tubicola. Each is gently curved and tapered, and has an elliptical cross-section at all parts of its length. The texture is quill-like, rigid, and translucent. The tube is, as usual, thickest over the middle portion, where the number of overlapping layers is greatest, and thinnest and most easily collapsible at the large end, where the most recent layer added projects from within the preceding. The usual annular lines representing the exposed edges of successive layers are well marked through- out the length. In the large tube, of which the measurements are given above, the annuli are mostly from 4.5 to 6 mm. apart. Locality. Off Mexico: Sta. 3424 (lat. 21° 15' N., long. 10G° 23' W.). Depth 679 fms. Bottom of grey sand with black specks. Bottom temp. 38° F. About a dozen tubes, half of them containing animals, were dredged 18 April, 1891. Off Mexico: Sta. 3425 (lat. 21° 19' N., long. 106° 24' W.). Depth 680 fms. Bottom of green mud and sand. Bottom temp. 39° F. A single specimen taken 18 April, 1891. HYALINOECIA TUBICOLA. 315 From H. tuhicola (Miiller), apparently so common farther south, this species is distinguished in having the branchiae begin farther forward and in their clearly greater length; in having the peristomium much larger in comparison with somite II; in the different proportions of the tentacles; and in the details of structure of setae and jaws. In the small H. juvenalis Moore the branchiae may similarly begin on somite XIX; but, among other differences, that form has conspicuous eyes, whereas the present one has none, and differs in the form and size of postsetal and presetal lips of the parapodia, in the fewer teeth of maxillae III, in the much smaller peristomium, which is only one third as long as somite II, and in the presence of compound setae on the first parapodia. Hyalinoecia TUBICOLA (0. F. Mtiller). Nereis tvbicola O. F. Mulleb, Zool. Danica prod., 1766, p. 217; Zool. Danica, 17S8, 1, p. 18, tab. 18, f. 1-6; Turton's Linnr, 1806, 4, p. 87; Bruguiere, Encyclop. mothod. Vers, 1827, 1, p. 134, tab. 55, fig. 7-12; Addouin k Milne Edwards, Ann. sci. nat., 1833, 29, p. 228; Grube, Actin. echin. wiirmer Mittelmeeres, 1840, p. 82; Thompson, Rept. Brit, assoc, 1843, pt. 2, p. 76; Pe.^ch, Ray soc. rept. Zool., 1844, 1843-1844, p. 508; Rept. Brit, assoc, 1844, pt. 2, p. 64; Johnston, Ann. nat. hist., 1845, 16, p. 6, fig. 1-6. Leodice tuhicola Savigny, Descript. Egypte. Hist, nat., 1809 [= 1822], 1, pt. 3, p. 52. Nereidonta tuhicola Blainville, Diet. sci. nat., 1828, 57, p. 447. Spio filicornis Delle Chiaie, Mem. anim. regn. Napoli, 1828, 3, p. 173, 176, pi. 45, fig. 6, 7. Eunice lubicola Fleming, Encycl. Brit., ed. 7, 1834, 7, p. 219; Landsborough, Excurs. Arran., 1852, p. 49. Onuphis tuhicola Saes, Beskr. og. lagtt., 1835, p. 48; Grube, Zur anat. kiemenw., 1838, p. 45, pi. 2, fig. 10; Oersted, Nat. tids., 1844-1845, 1, p. 405; Grube, Fara. annel., 1851, p. 44, 123; S.vrs, Nytmag. naturw., 1853, 7, p. 386, 391; Grube, Insel Lus.sin, 1864, p. 79; Quatrefages, Hist. nat. anneles, 1865, 1, p. 351; Ehlers, Borstenwiirmer, 1868, p. 297, pi. 13, fig. 1-14; Mobius, Jahresb. Comm. deutsch. meere, 1875, p. 168; M.^rion & Bobretzky, Ann. sci. nat., 1875, ser. 6, 2, p. 10; Benham, Chilton's Subantarc. i-slands of N. Z., 1909, 1. Polych., p. 245. Northia tvbicola Johnston, Cat. annelids Brit, mus., 1865, p. 136, 341; P.\rfitt, Trans. Dev. assoc, 1867, 2, p. 20. Hyalinoecia tuhicola Malmgren, Annulata Polychaeta, 1867, p. 67; Kupffer, Jahresb. Comm. deutsch. meere, 1871, p. 150; Sars, Bidrag Christ, fauna, 1873, p. 16; M.almgren, Goteb. vet. vitt. handb., 1874, 14, p. 85; McIntosh, Ann. nat. hist., 1874, ser. 4, 14, p. 200; Invert. & fishes St. Andrews, 1875, p. 123; Tauber, Annul. Danic, 1879, p. 103; Langerhans, Zeitschr. wiss. zool., 1879, 33, p. 241, pi. 15, fig. 26; Marion, Ann. sci. nat., 1879, ser. 6, 8, p. 17; Schmiedblberg, Mitth. Zool. stat. Neapoli, 1882, 3, p. 373; Wiren, Chaetop. Vega exped., 1883, p. 403; Levinsen, Vidensch. meddel. fores. Kjoben., 1883, p. 227; McIntosh, Challenger AnneUda, 1885, p. 335; Carus, Fauna Meditt., 1885, 1, p. 209; Pruvat, Arch. zool. exp(5r., 1885, .ser. 2, 3, p. 2.56, pi. 13, fig. 1-5; St. Joseph, Ann. sci. nat., 1898, ser. 5, 5, p. 241; McIntosh, Ann. mag. nat. hLst., 1903, ser. 7, 11, p. 557; 12, p. 164; Moore, Proc Acad. nat. sci. Philad., 1904, p. 144; Augener, Bull. M. C. Z., 1906, 43, p. 135; St. Joseph, Ann. sci. nat., 1906, ser. 9, 3, p. 199, pi. 4, fig. 75; Eisig, Fauna u. flora Golfes Neapol, 1906, 28, p. 215; McIntosh, British annehds, 1910, 2, pt. 2, p. 419, pi. 44, fig. 5-5b, pi. 64, fig. 5, 5b, pi. 65, fig. 15, pi. 75, fig. 11, pi. 84, fig. 8, 8b-8d; Izuka, Journ. Coll. sci. Imper. univ. Tokyo, 1912, 30, p. 97, pi. 11, fig. 1-4. Hyalinoecia plalyhranchis Grube, Monatsber. K. preuss. akad. wLss. Berlin, 1877, p. 527. Hyalinoecia artifex Verrill, Proc U. S. N. M., 1880, 3, p. 357. Onuphis gracilis Ehlers, Mem. M. C. Z., 1887, 15, p. 78; Levinsen, Vidensk. ud. hauchs, 1893, p. 331; Mabenzeller, Zool. ergebn., 1893, 2, p. 9; Roule, Camp. Caudan, 1896, p. 445. 316 THE ANNELIDA POLYCHAETA. Localities. Peru: off Aguja Point. Sta. 4653 (lat. 5° 47' S., long. 81° 24' W.). Depth 536 fms. Bottom of dark brown volcanic mud. Bottom temp. 4L3° F. 12 November, 1904. Numerous specimens. Off Panama: Sta. 3353 (lat. 7° 06' 15" N., long. 80° 34' W.). Depth 695 fms. Bottom of green mud. Bottom temp. 39° F. 10 March, 1891. A niunber of specimens of large size. Off Panama: Sta. 3356 (lat. 7° 09' 30" N., long. 81° 08' 30" W.). Depth 546 fms. Bottom of soft black mud. Bottom temp. 40.1° F. 23 February, 1891. Seven specimens. Off Panama: Sta. 3362 (lat. 5° 56' N., long. 85° 10' 30" W.). Depth 1,175 fms. Bottom of green mud, and sand, with rock. Bottom temp. 36.8° F. 20 February', 1891. Fifteen poorly preserved specimens. Off Panama: Sta. 3366 (lat. 5° 30' N., long. 86° 45' W.). Depth 1,067 fms. Bottom of yellow Globigerma ooze. Bottom temp. 37° F. 27 February, 1891. Three tubes. Off Panama: Sta. 3392 (lat. 7° 05' 30" N., long. 79° 40' W.). Depth 1,270 fms. Bottom temp. 36.4° F. Bottom hard. 10 March, 1891. Many tubes of which a considerable proportion contain animals. Tubes of small and intermediate sizes. To some are attached small actinarians, barnacles, and tubes of serpuhds. Off Panama: Sta. 3393 (lat. 7° 15' N., long. 79° 36' W.). Depth 1,020 fms. Bottom of green mud. Bottom temp. 36.8° F. 10 March, 1891. A number of tubes of varying size, mostly empty. Off Galapagos Islands: Sta. 3400 (lat. 0° 36' N., long. 86° 46' W.). Depth 1,322 fms. Bottom of hght grey Globigerina ooze. Bottom temp. 36.1° F. 27 March, 1891. Several tubes of large size containing badly preserved frag- ments of animals. The dentate spines of posterior somites appear somewhat more slender and curved, with the terminal teeth at a greater average angle with the axis of the shaft than in the specunens from the shallower depths off Panama. Off Galapagos Islands : Sta. 3407 (lat. 0° 04' S., long. 90° 24' 30" W.) . Depth 885 fms. Bottom of Globigerma ooze. Bottom temp. 37.2° F. Several tubes Uke those from Sta. 3400. 3 April, 1891. The above agree with specimens from the Atlantic. There seems to be considerable variation in the du-ection of the teeth of the stout hooked setae. In the material from off Panama many of these setae have the terminal teeth HYALINOECIA LEUCACRA. 317 projecting in the direction of the axis of the shaft instead of at a distinct angle with it, as more usual. This is a characteristic of Moore's H. tubicola stricta, dredged from off San Diego, Cal.; but in the present series of specimens this character is variable and is not correlated with a difference in the jaws as given for stricta. Many of the specimens have the setae of strictly typical form. In regard to the jaws it may be said that the specimens agree with the typical At- lantic form, the teeth of maxillae II, left outer plate, being mostly thirteen with sixteen as the maximum noted and twelve as the minimum. No individ- uals showed the high numbers occurring in stricta, namely eighteen for the left outer plate II and seventeen for the right. This species as now known has an exceedingly wide range, having previously been recorded from various parts of the North Atlantic off both the American and European coasts, and from the Mediterranean, Canary Islands, Azores, West Indies, off Brazil, New Zealand, Torres Strait, Japan, East Indies, and Africa. Hyalinoecia LEUCACRA, sp. nov.^ Plate 37, fig. 9, 10; Plate 38, fig. 1-3. Two incomplete specimens are in such poor state of preservation that a complete account cannot be given. This is a slender form having a maximum diameter of about 2 mm., exclusive of the parapodia. The median and posterior paired tentacles, which are broken off at the tips in one and absent from the other, seem to be of nearly equal size, the anterior paired tentacles being very much shorter. The ceratophores are long and relatively slender, though clearly stouter than the styles. Each is rather weakly annulate, the annuli long. The peristomium is much shorter and narrower than somite II, its length in the type being less than one half that of the latter somite. The anterior pairs of parapodia are longer than usual, the first pau' in particu- lar being conspicuously so and extending almost directly forwards much beyond the anterior end of the prostomium. The setae of the first parapodia are very numerous and closely crowded. They are much stouter than those of the posterior somites, dark-colored, acicuU- form, cui^ved distally, and at distal end with two blunt lobes or teeth with guards. (Plate 38, fig. 2). Acicula ending abruptly in very fine, transparent tips equal- XoikAs, white, aKpa, tip. 318 THE ANNELIDA POLYCHAETA. ling or a little surpassing the other setae. The acicula of the other parapodia also long and similarly ending in fine tips. Siinilar but smaller setae occur on the second and following parapodia; but, in addition, Umbate setae are present and a fascicle of pectinate setae that have unusually long stalks. The expanded tips of the pectinate setae have the usual cuneate outUne, each being Uke a funnel with a large sector removed, and with the free edge finely pectinate. (Plate 37, fig. 9). The Umbate setae are conspicuously bent at the base of the blade and the very fine tip is more or less curved, frequently hooked to some extent. (Plate 37, fig. 10). Farther caudad uncinate setae, or crochets, make their appearance. These are long and generally stout though varying consider- ably in thickness and in the curvature at the cervix. The teeth stand at a considerable angle with the axis, the upper and somewhat larger one stout and considerably curved. (Plate 38, fig. 1). The setae are aU proportionately long. The Umbate setae have the blades whitish in color so that the fascicles appear white tipped, giving a characteristic appearance to the species. In one specimen the maxiUae have the teeth wliitish. In the left outer plate III there are eleven teeth, on the inner thirteen. The teeth of the inner plate are coarser than those of the outer one. The halves of the mandibles seem to be entirely distinct, being only in weak contact. The white masticatory plates stand at a strong angle to each other, each extending obUquely cephalo- ectad. Each has a distinct notch on the ectal side, the plate being somewhat depressed or furrowed mesad from this. The stems are widest at the anterior end just caudad of the masticatory plate. (Plate 38, fig. 3). The somite on which the branchiae begin could not be determined. The longest branchiae about equal the width of the somites. The tubes have the structure and appearance usual in the genus. The maximum diameter at the large end is about 5.5 mm. The rings representing the Imiits of successive layers are mostly from four to five millimeters apart. The color of the animals is very dark excepting a pale median dorsal and a median ventral band. Some of the glandular pads are also pale. The Umbate setae white at tips. Locality. Off Mexico: Sta 3418 (lat. 16° 31' N., long. 99° 52' 30" W.). Depth 660 fms. Bottom of brown sand with black specks. Bottom temp. 39° F. 11 April, 1891. Two specimens. Characterized especially by the very long first parapodia and their numer- ous stout setae, and by the structure of the setae of these and the other para- podia. LEPTOECIA. 319 Entangled in the setae of one of the specimens were a number of vegetable fibres and cells. These were chiefly stellate idioblasts of large size, probably from some decayed terrestrial plant. This is not at all surprising in view of the fact that Mr. Agassiz found terrestrial debris so abundant at all depths in this region. In his letter concerning the explorations of the Albatross in this region he says: "Nearly every where' except on the face of the Galapagos slope we trawled upon a bottom either muddy or composed of Globigerina ooze, more or less contaminated with terrestrial deposits, and frequently covered with a great amount of decayed vegetable matter. We scarcely made a single haul of the trawl which did not bring up a considerable amount of decayed vegetable matter, and frequently logs, branches, twigs, seeds, leaves, fruits, much as during our first cruise." (Bull. M. C. Z., 1891, 21, p. 190-191.) Leptoecia, gen. nov.' Prostomium with two short, tliick, frontal tentacles and five posterior, or dorsal, tentacles each provided with a ringed ceratophore. A pair of cushion- like palpi separated ventrally by a median fissure. Peristomium simple and very long, bearing no tentacular cirri. Body flattened, especially posteriorly; not obviously narrowed cephalad, but at the caudal end narrowed acutely. Anus terminal on pygidium. Anal cirri apparently two. First parapodia large, extending directly forwards along the sides of the peristomium but not attaining the prostomium. Ending distally in a flattened process and bearing unjointed hooded crochets. Ventral chri soon becoming reduced to pads. Dorsal cirri decreasing in size caudad and disappearing in the posterior region. On the anterior parapodia, excepting the first, occur Umbate and deUcate pectinate setae, while farther caudad there occur strong hooded crochets and other limbate setae. Maxillae of the usual number and arrangement, with all parts well developed. Mandibles also well developed, with long shafts and rather narrow, subfoUate, masticatory plates. Branchiae none. Tube thin, translucent, without foreign material. Genotype. — L. abyssorum, sp nov. ' XfBTos thin, and oMa, house. 320 THE ANNELIDA POLYCHAETA. This genus seems unquestionably close to Hyalinoecia. From this it differs especially in wholly lacking branchiae, and in the much greater relative length of the peristomium, which the first parapodia do not surpass. Leptoecia abyssorum, sp. nov.^ Plate 36, fig. 1-6; Plate 37, fig. 1-8. The general color is dull yellowish. There is a whitish, median ventral, or neural line. The parapodia are a lighter yellow and the tentacles, cirri and ventral glandular areas are pale. The type is a slender specimen in three fragments which have a total of about seventy somites. The fragments together have a length of about 42 mm. The width does not vary much excepting at the extreme caudal end, where the body narrows to a point. The anterior end is not narrowed. The width in the middle region of the body is 1.75 mm. The prostomium is narrowed from behind cepbalad, being bluntly subconi- cal. Anteroventrally the prostomium presents four lobes, being divided by a median subvertical furrow and again by a transverse furrow. The upper lobes are essentially frontal tentacles; they are low and rounded, subhemi- spherical, and pale in color. The lower lobes are larger and correspond to the palpi, e.g., in Onuphis. They are large, smooth, thick rounded pads on the ventral side. They are contiguous at the middle line and extend transversely to, or bulge out a little beyond, the lateral borders of the prostomium. The anterior paired tentacles do not reach the caudal end of somite I. The cerato- phore is short and but vaguely annulate. The style is proximally as thick as the ceratophore and narrows distad to the free end. The posterior paired tentacles are inserted caudoventrad of the anterior paired ones. They have the distal portion of their styles broken off, so that their length camiot be given. The ceratophore is only indistinctly annulate. The style at base is as thick as or a Httle thicker than the ceratophore and narrows gradually distad, as usual. The median tentacle is inserted but Uttle caudad of the level of the posterior paired ones from each of which it is farther removed than the latter is from the corresponding anterior paired tentacle. It is removed from the caudal edge of the prostomium by its diameter, or more. Its style is broken off. The cerato- phore is vaguely annulate and is thicker than that of the posterior laterals. (Plate 36, fig. 1, 2). 1 abyssus, depth. LEPTOECIA ABYSSORUM. 321 The peristomium is decidedly wider than the prostomiuni and is very much (nearly one and two thirds times) longer. The anterior margin above is straight, or nearly so. Laterally it curves forward and embraces the sides of the pro- stomiuni. The lower lip consists of a rather small, more elevated, subtriangular area set off on each side by a depression extending mesocaudad from the anterior margin. Its anterior border protrudes forward and the edge is straight. (Plate 36, fig. 1, 2). The second somite (first metastomial) consists of a wider anterior division, from which the parapodia arise, and a narrower caudal ring ; its total length is about equal to that of the peristomium. The succeeding somites decrease gradually in length to the fifth, which is four fifths as long as the peristomium or as the second somite (first metastomial), the followmg segments through the middle region running of the same length, or nearly so. In the posterior region they become much shorter, only half as long as the fifth, etc., and m the narrowed caudal division only a third or fourth as long. The somites are dor- sally moderately arched, ventrally more nearly flat, the body being compressed dorsoventrally, and in the type mostly strongly so at the caudal end. The first parapodia are attached laterally at the anterior border and nearer the ventral surface of the somite; they extend directly forwards or but very slightly ectad and close to the side of the peristomium; they are cylindrical and long, attaining, or very nearly attaining, the anterior end of the peristomium. The notocirrus is attached dorsally a little distad of the middle; it is slender, moderately tapering, and short, not extendhig beyond the distal end of the parapodiiun. The neurocirnis is attached on the ventral surface farther toward the base; it is slender and short, not extending beyond the beginning of the distal third of the parapodium. The parapodium at the distal end presents only a slight presetal elevation; Ijut caudad of the setae there is a prominent, wide, distally widely rounded or subtruncate, postsetal lobe. (Plate 37, fig. 1). The second parapodia are abruptly very different; they are similarly attached at the anterior end but extend more ectad and are very much shorter. Theh notocirrus is of a similar form and size but is attached proportionately decidedly farther proximad. The neurocirrus is attached at the veiy base and is proxi- mally stouter than that of the first parapodia. The postsetal process is more slender, strictly cirriform, and is much longer than in the first foot. (Plate 37, fig. 2). The tliird parapodia are attached in the same manner as the second ones, have a similar dkection, and are of essentially the same size. The noto- cirrus and the postsetal process are the same in form, size, and position; but the 322 THE ANNELIDA POLYCHAETA. neurociiTus is reduced to a low rounded elevation or tubercle. (Plate 37, fig. 3). On succeeding parapodia caudad the notocirri gradually become reduced both in length and diameter, finally in the posterior region appearing as mere rudi- ments or tentacles, and then quite disappearmg. (Plate 37, fig. 4). The neurocirrus is reduced to a scale-hke body in the glandular area, as usual in Onuphis. The postsetal process caudally becomes gradually reduced, appear- ing soon as a merely slight, rounded, elevation, and not at all evident after the thirteenth parapodia or near them. The parapodia after the third become attached near the middle of the somite and shift to a more dorsal position, as usual. Tlu-ough the middle region they continue as moderately prominent processes, but in the posterior region they become more shortened. Through- out the length the parapodia continue to project in a distinctly ectocephalic direction. The ordmary crochets, occurring on all but the more anterior somites, are long, coarse, transparent setae, which are straight except toward the distal end , where they are gently curved; they are of essentially uniform diameter until narrowed in the usual way below the cervix, or they may appear a little thicker just below this region ; the medulla is finely, obliquely fibrillate in the distal portion; they are bidentate, the teeth obUque and subparallel, rather slender and acute, with the subapical one the longer; the membranous guards rise conspicuously above the apical tooth and are narrowly, subacutely rounded at the tip. (Plate 37, fig. 7). The dehcate pectinate setae are numerous and form a prominent fascicle, more dorsal in position ; the stalks are comparatively long, and the end-piece is cuneate in outline, but forms really a hollow half cone, with a fringe of uniform and rather short teeth along the distal edge. (Plate 37, fig. 5). Below the fascicle of pectinate setae is a series typically of four long, stout, Itmbate setae; each of these is typically moderately bent near the begin- ning of the distal third, which is acuminate and ends in a fine tip; the seta is bilimbate, the wings widest at the bend, and from there they narrow each way and so soon disappear. (Plate 36, fig. 5, 6). The acicula are pale; they are stouter than the coarse limbate setae and most of the buried portion is of nearly uniform thickness; a little below the surface each aciculum begins to narrow, and above the surface is rapidly attenuated to a fine tip. (Plate 37, fig. 6). On each of the first parapodia there are three stout setae or crochets of special character; these are weakly and moderately curved, are unjointed, and are apparently rounded, with but a slight indication of a tooth set off by an incision below tip; each tip is protected by two membranous guards that rise above its LEPTOECIA ABYSSORUM. 323 apex, the guards narrowing abruptly at level of tip of seta, which it enfolds proximally; the medulla is densely- fibrUlate, the fibrillae being somewhat oblique and usually very dense excepting in the distal region. (Plate 37, fig. 8). No crochets of this type are found in the tj'pe on the second parapodia, but in their place occur stout setae gradually attenuated distad to a fine flexible tip and narrowly lunbate along one side, these on other parapodia caudad occurring among the shorter of the usual bilimbate setae. The maxillae are thin and translucent, with the edges and the tips of the first pair dark. Maxillae I have the carriers usually united along the middle line to form a plate longer than wide; the plate on each side toward the anterior end is weakly incur\ed and conunonly moderately bulging, caudad; the plate is uniform in the tj-jje, the elevated triangular area being set off anteriorly only vaguely; the blades are of the usual falcate form, the terminal portion slender and well cur\-cd. IMaxilla II of the right side has twelve teeth which gradually increase in size distad, the most distal being conspicuously large and well sepa- rated ; the inner plate on the left side has thirteen teeth also increasing in size distad, and the outer plate has eighteen teeth, of which the most distal one is abruptly decidedly longer and stouter. Maxilla III of the left side has eleven teeth, that of the right side has ten teeth. (Plate 36, fig. 3). The mandibles are of good size but are thin and translucent. The masticatory plates are narrow mesaUy and subclavately enlarged ectad; they are white and hard; below the ectal end of each is a conspicuous notch separating it from the expanded sup- porting part of the stem. The anterior edge of each plate is nearly smooth, but shghtly uneven, the two meeting at an angle of less than 90°. The stems are long and, excepting at the ends, are parallel and of uniform width ; they are weakly united anteriorly and are pale throughout, excepting for a short but conspicuous narrow black stripe on each along its mesal edge at the anterior end. (Plate 36, fig. 4). The tube is straight, flexible, and transparent. It presents on each side a slender, rather stiff, cyhndrical, supporting rod. The membrane between the two rods is thin and transparent. The tube is flattened at right angles to the plane embracing the axes of the two supporting rods, its cross-section being some- what lenticular. The transverse diameter is 3.2 mm. Locality. Between the Galapagos and Peru: Sta. 4647 (lat. 4° 33' S., long. 87° 07' 30" W.). Depth 2,005 fms. Bottom of fight grey and brown Globigerina ooze. Bottom temp. 35.4° F. 9 November, 1904. One specimen. 324 THE ANNELIDA POLYCHAETA. LUMBRINEREIDAE. In this family the body is more or less elongate and cylindrical, ordinarily narrowed anteriorly but more strongly so posteriorly; distinctly segmented. The skin is of tough consistence and is smooth and strongly iridescent. The prostomium is most commonly conical, or sometimes more rounded. Both tentacles and palpi are most conunonly absent, or three tentacles may be present in the Lysaretinae. Eyes present or absent. First two somites without appendages and smooth, or the second sometimes setigerous. Mouth commonly having two hps. Parapodia uniramous, well developed. No ventral cirri are present, while the dorsal cirri are either fohaceous in character or rudimentary. Branchiae only rarely present (Ninoe). The setae may be of various types. In some all the setae are of a simple, capillary, laminate type, while in other cases crochets, or crochets and composite setae are present. The proboscis is armed with a pair of mandibles, or these may be obsolete, and with a definite and commonly, but not always, even number of maxillae. Both anterior and posterior regions may be regenerated in some forms at least (Lumbrinereis, Halla) . The lumbrinereids occur in mud and sand and under stones in the Uttoral zone, as well as down to depths exceeding two thousand fathoms, as in the case of Lumbrinereis abyssorum secured by the Challenger off the west coast of South America at a depth of 2,225 fathoms. Many have been taken from the stomachs of fish. The species of certain genera are normally commensals or parasites during all or the early part of their lives. Labrostratus parasiticus was found by St. Joseph (Ann. sci. nat., 1888, ser. 8, 5, p. 219, 221) occurring in the general body-cavity of various sylhds, such as Odontosyllis ctenosoma, Eusyllis nionili- cornis, Pionosyllis lamelligera, Syllis prolifera, and Grubea clavata. In this species the adults may be free and non-commensal. Oligognathus bonelliae Spengel occurs ia the body cavity of the gephyrean BonelUa (Spengel, Mitth. Zool. stat. Neapel, 1882, 3, p. 15, pi. 2-4). Haematocleptes terebellidis Wiren seems to live a completely parasitic Ufe in the blood sinus of the wall of the stomach of Tere- bellides stromi (Bih. K. Svenska vet. akad. Handl., 1886, 11, no. 12). This form shows a strong reduction of the maxillary apparatus, an atrophy also evident, but less marked, in Labrostratus. Labidognothus parasiticus Caullery (Compt. LUMBRINEREIDAE. 325 rendus Soc. biol., 1914, 77, p. 490) also lives parasitically in a terebellid, but the regressive modifications are much less pronounced. Ophiuricola cynips, described by Ludwig (Zool. anz., 1905, 29, p. 397) as parasitic and galligenous inswelUngs on the arms of the deep-sea Ophiura tumulosa (Liitken and Mortensen) is too briefly characterized to make it possible definitely to place it, though it may be a lumbrinereid. Key to Genera. a. Dorsal cirrus rudimentary Lumbrinereinae. b. Parasitic forms; jaws more or less atrophied. c. Eyes none (parasitic in Terebellides) Haematocleptes Wii6n. d. Setae not emerging from parapodia; maxillae I strongly atropliied. dd. Setae emerging freely from parapodia, two series of fascicles; maxillae I well developed. Labidognathus Caullery. cc. Four eyes present. d. Lower jaws moderately developed (parasitic in Syllidae) Labroslratus St. Joseph. dd. Lower jaws more atrophied (jmrasitic in Bonellia) Oligognathus Spengel. bb. Not parasitic; jaws normally developed (excepting in Biborin). c. With only simple, mostly capillary and laminate setae, no hooked spines or crochets. d. First two somites achaetous. e. With no maxillae Biborin Chamberlin. ee. Maxillae well developed. /. Blades of maxOlae I in form of stout hooks which may be mesally denticulate only at base. g. Third and fourth maxillae reduced to hooks. h. Maxillae I with three slender supports Loranda lunberg. hh. Maxillae I with but two supports Drilonereis Claparede. gg. Third and fourth maxillae dentate plates, not reduced Arabella Grube. }}. Maxillae I not in the form of hooks or strongly uncate plates; normally dentate along entire mesal edge. g. With four pairs of maxillae Pterothrix, gen. nov.' gg. With five pairs of maxillae. h. Small no tocirri present; setae few, dentate at base of limbus .. TVotoaVrjis Schmarda. hh. No notocirri obvious; setae simply limbate, not dentate. .. .Notopsiius Ehlers. dd. First somite only achaetous; five pairs of jaws Aracoda Schmarda. cc. Crochets or compound setae or both present, more than one in most parapodia of posterior region. d. With digitate branchiae on setigerous lobes of parapodia Ninoe Kjnberg. dd. No branchiae. e. Crochets single, sometimes aciculiform but always hooded. /. First maxillae in form of strong hooks; III and IV not dentate. .Cenogemts, gen. nov. ff. First maxillae not in form of hooks, strongly dentate, with long posterior supports. Guards of crochets strongly asymmetrical Cenothrix, gen. nov. ee. Crochets not single. /. With four pairs of maxillae. Maxillae I in form of stout hooks; crochets numerous in posterior region. Lumbrinereis Blainville. //. With five pairs of maxillae Larymna Ivinberg. aa. Dorsal cirri well developed, usually foliaceous Lysareiinae. b. Prostomium anteriorly with two laterally directed processes Enonella Stimpson. 66. Prostomiiun with no such anterior processes. c. Carriers of maxillae I short, forming broad blades Lysarete Kinberg. cc. Carriers of maxillae I long and filiform. ' Genotype, Nolocirrua scoticus Mcintosh. 326 THE ANNELIDA POLYCHAETA. d. With two complete somites apodous. Two eyes and five pairs of maxillae Halla A. Costa. dd. With one complete somite apodous, a second incomplete somite may be evident ventrally. e. With six pairs of maxillae Danymene Knberg. ee. With five pairs of maxillae Oenone Savigny. The key follows the general lines indicated in Grube's revision (Jahresb. Schles. gesellsch., 1879, 56, p. 78), but with such differences as further knowledge- has rendered necessary. There is considerable uncertainty with reference to some genera that have been proposed, and some here suppressed may be found to have differential generic characters not evident in the published accounts, while others may have to be abolished. Synonymy of Genera. The genus Enonella, founded by Stimpson (Invertb. Grand Manan, 1853, p. 34, f. 25, 25 a-d) for a species (bicarinata) found at Grand Manan is far too incompletely described to be placed with certainty. It appears to belong in this group. It is readily distinguished from other lumbrinereids by the form of the prostomium with its two laterally directed processes in front. Lais Kinberg (1865), being preoccupied in Acaridea, was replaced by Ehlers with Notopsilus (1868). As the type-species, fulgida Savigny, of Aglaura Savigny (1820), which, being preoccupied, was later replaced by Aglaurides Ehlers (1868), has now been shown to be the same as lucida Savigny, the type of Oenone, the first name and its substitute lapses. There is ground for thinking that fonensis Kinberg may also be the same as lucida, in which case Danymene will also lapse. It is kept apart at present on the basis of the supposed difference in the numlier of maxillae. Cirrobranchia Ehlers is in synonomy with Halla A. Costa, as is also Plio- ceras of Quatrefages. Maclovia Grube is merged with Arabella Grube. Zygolobus Grube (\vritten Zygophyllus in the description of plates) is in- cluded in Larymna Kinberg. Bidenkap (Kgl. Norsk, vid. selsk. Skr., 1907, 1906, no. 10, p. 16) has established the Uncinisetidae for his genus Unciniseta characterized by having biramous parapodia bearing only crochets and lacking cirri. It is apparently near the Lumbrinereidae and Dorvilleidae ; but, unfortunately, the character of the proboscis in the type and only known species, U. sivenanderi Bid., is not indicated. LUMBRINEREIS BIFILARIS. 327 LuMBRiNEREis BlainviUe. Diet. sci. nat., 1828, 57, p. 486. Scoleloma Blainville, ibid., p. 492. Lumbriconereis Grubb, Archiv. naturges., 1851, 17, p. 45. Eranno Kinberg, Ofvers. K. vet. akad. Forh., 1865, no. 4, p. 567. LUMBRINEREIS BIFILARIS Ehlers. Plate 60, fig. 6-9; Plate 61, fig. 1. Lumbriconereis bifdaris Ehlers, Abhandl. K. ge.sellsch. wiss. Gottingen. Math. phys. klasse, 1901, p. 139, pi. 18, fig. 1-10; Moore, Proc. Acad. nat. sci. Philad., 1911, p. 291. In a specimen from Sta. 3418 there are 135 segments exclusive of the head. The length is about 107 mm., with the maximum width, exclusive of parapodia, 6 mm., this being attained near the twelfth somite. But this width changes l^ut little and only very gradually caudad, the body appearing almost uniform in width; a little in front of the caudal end the width is 5 mm. This is an ex- ceptionally robust specimen, but others form a complete transition to the more slender and usual form. Prostomium acuminate from the base as usual, sides a little convex, and anterior end acutely rounded; depressed, the ventral surface flat, with a median longitudinal furrow, and the dorsal surface moderately convex, with a slight crescentic elevation at base; thick at base, decreasing in thickness distad; wider across base than long. Peristomium crossed on lower part of sides and ventrally by a series of fine sulci which laterally are faint but ventrally become distinct and end in an emargination in the anterior border. Palpal cushions well marked, simple, rounded tubercles, or pads, which are wider than long. The parapodia of the specimens here listed have the usual character. In the anterior parapodia there is a distinct, postsetal, foliaceous lip which is at first low and extends proximad along the ventral surface, and a smaller, presetal, less foliaceous lip as well. In proceeding caudad the postsetal lip becomes more and more elongate and finger-like, extending in a caudal direction; the presetal lip more slowly elongates, but in the posterior region is as long as the postsetal process and extends more or less dorsad; the processes are slender and mobile and commonly much exceed in length the parapodia proper, this showing con- siderable variation in the preserved specimens. Both the hooked and the capillary setae are long. The limbate capillary setae are distally of the form shown in Plate 60, fig. 8, 9. A typical hooked seta 328 THE ANNELIDA POLYCHAETA. is represented in Plate 61, fig. 1. The acicula are blackish and often protrude conspicuously beyond the surface of the parapodia. The mandibles are opaque and brown except for anterior tips which become darkened, blackish; the masticatory plate is deeply incised anteriorly and the plate is marked, as is common, with a series of transverse parallel lines as shown in the figure. The relative width across the anterior end is greater than, e.g., in L. japonica Marenzeller and L. japonica index Moore. (See Plate 60, fig. 6). The maxillae are black; the second pair are provided with four or five teeth (rarely with six) , which decrease in size caudad and are of the general form shown in Plate 60, fig. 7; the third pah- are conspicuously narrowed into a slender process at the mesal end, and are unidentate. The color throughout is a more or less yellowish brown. Localities. Off Mexico: Sta. 3418 (lat. 16° 31' N., long. 99° 52' 30" W.). Depth 660 fms. Bottom of brown sand with black specks. Bottom temp. 39° F. 1891 Exped. Two specimens and some fragments. Off Mexico: Sta. 3424 (lat. 21° 15' N., long. 106° 23' W.). Depth 679 fms. Bottom temp. 38 F. 18 April, 1891. Two specimens. Gulf of CaUfornia: Sta. 3435 (lat. 26° 48' N., long. 110° 45' 20" W.). Depth 859 fms. Bottom of brown mud with black specks. 22 April, 1891. One specimen of about the same size as those from Sta. 4631. Between Panama and the Galapagos Islands: Sta. 4631 (lat. 6° 26' N., long. 81° 49' W.). Depth 774 fms. Bottom of green sand. 3 November, 1904. Two smaller specimens, of which the larger has a maximum width of 3.25 mm., exclusive of the parapodia. This species seems to occur rather abundantly from southern Chile north- ward at least to Monterey Bay, and its bathymetrical range is also correspond- ingly great, it having been recorded at depths from 36 to 2,182 fms. It is characterized by its conspicuously elongate parapodial processes. The maxillae would at first seem to separate these specimens clearly from the form described by Ehlers. In Ehlers's figures, the maxillae are given the form seemingly widely different from that usual in the genus ; but an appearance very similar is secured when the pieces are viewed edgewise, and I am inchned to think the artist has so drawn them rather than that the type is abnormal as supposed by Moore. The type is a very small specimen, and proper orientation of the maxillae, if drawn in situ, would be difficult. A specimen of about the same size as Ehlers's type has the prostomium of the more elongate propor- tions given by that author, so it is Ukely this difference is one due to age. CENOTHRIX. 329 Cenothrix, gen. nov.^ Prostomium subcorneal or ovoid, smooth, devoid of tentacles or palpi. Body elongated, with numerous distinct segments, tapering both anteriorly and posteriorly. First and second somites lacking parapodia and setae. Nuchal processes not evident. Parapodia essentially unii'amous, the notopodium reduced to a slight tubercle. Ending in a finger-like, postsetal process, but with no presetal process. All setae simple, partly limbate, and partly of the stout, crochet type wdth membranous guards, but the latter without teeth or hooks. Limbate setae in all parapodia and one crochet in each parapodium excepting the most anterior. Setae in type-species few and largely definite in number. Five pairs of maxillae. The carriers of the first pair extended caudad into long, slender, tendon-Uke processes, the plates dentate, unequal. Maxillae II, III, and IV dentate and unequal. Maxillae V reduced to simple hooks. Man- dibles mesally in contact in the broad anterior region, the stems short and scarcely narrowed caudad. Genotype. — Cenothrix mutans, sp. nov. In the characters of the jaws this genus falls into Grube's Eimicea Priog- natha of group B (Jahresb. Schles. gesellsch., 1879, 56, p. 80), including Drilon- ereis, Arabella, etc., but it differs in having setae of two main types, in which respect it agrees with genera of his group A. The crochets, however, are of a peculiar structure and, furthermore, do not increase in number caudad and in the posterior region occur to the exclusion of the limbate type. Thus it differs from LarjTnna Kinberg (Zygolobus Grube), e.g., in the greatly elongate, spine- like, stems of maxillae I, in the edentate character of the crochets, and in the uniform distribution of limbate setae on all parapodia ; and, on the other hand, it differs at once from Ai'abella in having setae of the crochet-type at all. It is, I beheve, close to Notocirrus Kinberg, the tyj^e of which also comes from the South Pacific region; but, particularly in view of some uncertainty in regard to import- ant details in the type of Notocirrus, I have felt it necessary to keep the forms apart. The spine construed by Schmarda as a hooded crochet in his type- species differs from that in Cenothrix in being distally bidentate and in the much smaller, rounded membranous guards. ' Kawos, new, strange, and epi|, bristle. 330 THE ANNELIDA POLYCHAETA. Cenothrix mutans, sp. nov.^ Plate 61, fig. 1-9; Plate 62, fig. 1. The type as preserved is throughout grey, in part of a weak flesh color or deUcate rose tinge. The body is elongated and slender, terete. It is tapered at the ends, but elsewhere is nearly of uniform diameter, being but shghtly thicker anteriorly than posteriorly. The length is approximately 107 mm., the maximum width, exclusive of parapodia, 1.6 nmi. The number of somites is about 280, the coiled condition of the type rendering exact counting difficult. The prostomium is ovate, clearly longer than wide, with the anterior end narrowly rounded. A little flattened dorsoventrally. Surface very smooth. On the ventral surface there is a weak. median longitudinal furrow which does not reach either end and is bounded laterally by slight, broad ridges, which are confluent caudally in front of the mouth. Palpi not distinct. Eyes none. (Plate 61, fig. 4). The peristoiuium is set ofT from the prostomium by a deep constriction. It is much shorter than the prostomium, but is wider. It and the second somite together are about two thirds as long as the prostomium. The outline in pass- ing from prostomium to peristomium is abruptly changed, but from the peri- stomium caudad it is evenly continuous. Both peristomium and the second somite are apodous. The peristomium is much longer than the second somite laterally, as it there curves conspicuously forwards, but is slightly incurved at the middle above. On the ventral side it is but little longer than the second somite and is crossed longitudinally by a few distinct sulci. The second somite is of nearly uniform length above and below, and is throughout deeply sepai-ated from the peristomium. (Plate 61, fig. 4). The succeeding somites are all simple and regular, and are smooth except- ing for a few weak, often somewhat oblique, sulci crossing the somites longi- tudinally and evident only under the microscope. The cuticle has the usual shining and iridescent appearance. A few sulci may be more distinct in the middle and posterior regions. Each parapodium is inserted in a shar]:)ly marked furrow crossing the somite longitudinally. The somites increase in length to about the seventeenth, after which the length is uniform, or nearly so, to the caudal end of the body. The somites, more particularly in the anterior region, curve forwards on each side just in front of the parapodium. ' mutare, to change. CENOTHRIX MUTANS. 331 The pygidium has a highly peculiar form in the type which may possibly be the result of regeneration. It is abruptly ver>^ much narrower than the preceding somite. It presents a basal di\'ision, which has a convex surface and narrows caudad and may represent a distinct somite, and a more slender, cylindrical, distal division, which bears at its distal end two stout cirri, which are contiguous at the base, are very short, in length less than the diameter of the adjoining region of the pygidium, and are bifid at the distal end. The parapodia are strictly lateral and about equidistant from dorsal and ventral lines. All are small, the most anterior ones being smallest, while the caudal ones are not reduced. All are short and cylindrical with no distinct presetal Up but with a very conspicuous postsetal finger-like process which is cylindrical, or rather slightly conical, and rounded at the tip. The postsetal process extends ectocaudad. It is of the same form and proportionate size throughout the body. The notopodium is represented by a slight tubercle above at the base of the neuropodium. No cirri are evident. No branchiae at all. (Plate 61, fig. 9). The nem-opodial acicula are normally two in number. They are stout at base and rapidly narrow to an acute fine tip. Each is slightly curved, with the concavity ventrad. (Plate 61, fig. 5) The more dorsal aciculum is pale yellow excepting the slender tip, which is colorless. The ventral aciculum is pale yellow proximally, but toward the tip becomes much darker brown, the tip colorless, as in the other. The setae are all simple and are of two types, capillary ones and stout spines. Of these the former are colorless, the latter yellowish. The capillary setae are all of the usual bilimbate type and all are bent a httle above the proximal end of the limbate region, some abruptly so, or geniculate. In the latter type a limbus, as seen in side view, is proximally broad, narrowing gradually distad, and fading out at base of the long slender tip; at the base along the convex free margin is a series of projecting teeth or scales, the edge elsewhere smooth. (Plate 62, fig. 1). In the other type the limbi are narrower and lack the scales, or have these but obscurely indicated and not projecting at all as teeth. (Plate 61, fig. 8). In the middle region a parapodium has ordi- narily but one of the more strongly curved, scale-bearing, limbate setae, and only two of the other, smooth Umbate, tyi^e. Of the stout spines, never more than one seem to be present in any parapodium. These are yellow in color throughout and are stout and curved. Each of uniforai diameter excepting at the distal end, where it narrows conicaUy and is wholly without terminal teeth or subapical spm- or process; the membranous guards are very unsymmetrically 332 THE ANNELIDA POLYCHAETA. developed, one being short and not surpassing the tip of the seta, while the other one, attached on the opposite side, is very much prolonged beyond it and is narrowed distad into a slender tip. (Plate 61, fig. 6, 7). How far forward the crochets extend was not satisfactorily determined. There are five pairs of maxillae, which are all dense black in color. In maxillae I the carriers are clavately widened at the anterior end, narrowing strongly caudad into very long, slender, chitinous spines which in situ extend back into the tenth somite and narrow very gradually, parallel, or nearly so; each spine appearing a httle incurved just caudad of the expanded end, where the two come in contact. The dentate plates are large, subtriangular, with the apex cephalad, unsymmetrically developed; the left plate is broader than the right and bears teeth along its entire mesal edge as present in the type, though it appears broken off at the distal end and may in that part have had a smooth edge; these teeth are large, retrorse, and eight in number; the right plate with eight smaller teeth along the mesal edge in a series that extends from the proxi- mal end only to the middle, leaving the distal acuminate half smooth. Maxillae II are also unsymmetrically developed, the right one being much larger; it presents two arms meeting at an acute angle anteriorly; the inner arm extends proximad along the mesal side of maxillae II, the base of which it nearly attains, and bears a series of fifteen or more teeth; the anterior arm is shorter and ex- tends down the outer side of the second maxilla. The much smaller left maxilla II is also bent into an angle into which the left maxilla I extends; the inner arm is short, extending but slightly down the mesal side of the first maxilla, and bears seven teeth ; the outer arm is very much smaller. Each maxilla III is similarly bent into an angle fitting about the anterior end of the corresponding maxilla II; the inner arm is also the longer and bears about five teeth. The right plate the larger. Maxillae IV are likewise unequal, the right plate being the larger. The right plate bears three slender, acute teeth, and a fourth, the most anterior, blunter one. The left plate presents above a single slender, bifid tooth and below a rounded prominence bearing a minute acute point. The fifth maxillae are reduced to simple hooks, each hook being long, slender, and evenly curved, and arising from a heavier basal piece. (Plate 61, fig. 2). The mandibles are black in color like the maxillae. Each one is a short, strongly clavate piece, narrowing caudad, and in contact with the other plate anteriorly; anteriorly the inner edges diverge from the point of contact and form an acute reentrant angle; the anterior end of each is truncate. (Plate 61, fig. 3). Locality. Easter Island. Shore. 20 December, 1904. One specimen. CENOGENUS DESCENDENS. 333 Cenogenus, gen. nov.^ Prostomium conical, smooth, devoid of processes and eyes. Two first somites lacking parapodia and setae. A conical nuchal process present at anterior edge of first segment above, this often retracted. Four pairs of maxUlae present, these well-developed plates, but all edentate, or the second alone with dentiform processes. First pair in form of strong hooks; carriers short, without slender posterior supports, or these obsolete. Mandibles united mesally in the broad anterior region, where they have well-developed dental plates; stems slender and short, tapering caudad. Parapodia essentially uniramous. Distally with a short, finger-like, post- setal process, but with no presetal process. Notocirri abortive. All setae simple, in anterior region exclusively of a slender hmbate form, but in posterior region with in addition a single, stout, crochet-formed, hooded seta in each parapodium, the guards of this rounded and short. Genotype. — C. descendcns, sp. nov. Cenogenus descendens, sp. nov. The body is but little narrowed cephalad, more strongly so caudad. Strongly convex dorsally, notably less so ventrally. Prostomium conical, broader than deep, and sometimes appearing much compressed dorsoventrally ; short, the width equalUng or exceeding the length. Smooth throughout. The anterior region flattened, or sometimes a Httle con- cave beneath in front of a moderately bulging basal region. Much exceeding the combined length of the first two segments. Peristomium set off by a deep sulcus from the prostomium. Dorsally it is twice as long as the second somite. Beneath it usually protrudes ventrad as a swollen transverse ridge, or lower Up, with a rounded lobe extending forward at each end and curving about the mouth to meet that of the other end in the front of the mouth-opening. Swollen all the way around, so as to rise above the level of the second somite dorsally also. Narrowest at sides where it is crossed longitudinally by a few sulci. Second somite longer dorsally than ventrally. Succeeding somites simple, regular, and smooth. They are of ahnost uniform length from the first setigerous caudad, all short. Form of pygidium unknown. - Kaivos, strange, and yki'v^, jaw. 334 THE ANNELIDA POLYCHAETA. Parapodia lower on first few segments than on the following ones. Nearer the ventral surface than to the more convex dorsal one. In general short and cylindrical, those of the most anterior segments much reduced in length. With- out cirri. No trace of a presetal process, but a distinct postsetal process present. This cylindrical, slender, finger-like, and short, being considerably less than the diameter of the parapodium. Acicula of neuropodium nonnally three in number, these stout, straight, and tapering distad to an apex that is not fine, this acute but with its sides convex. Of these acicula two are ordinarily deep black in color or paler only at tips, the third fighter, more brownish. The ordinary setae distally become thin and blade-Uke, this region obliquely finely striate and narrowing to a fine tip, this distal thin region gently doubly curved, but not at all geniculate and not at all dentate at base. In each of the posterior parapodia there is, in addition to the ordinary setae, a single stout spine at apex narrowed in a short, distally rounded tip protected by membranous guards, the latter short and roundetl; the protected tip in some cases appears to be incised or narrowly divided. The setae are dark brown proximally and pale distally. There are four well-developed pau-s of maxillary plates, none of which bear true teeth. All are black throughout. The carriers of the first maxillae with the posterior stems short; no posterior supports, or these rudimentary, if present being short, thin and pale. Hooks of first maxillae longer than carriers, stout and evenly curved. Second maxillae stout, heavy plates lying contiguously between the hooks of I ; each presents ventrally two large, stout, rounded proc- esses, one near middle and one toward anterior end. Plates of III and IV without teeth or processes. None of the cotypes is complete posteriorly. Mandibles with masticatory plates very large, the stems short and slender, shining white ventrally. Greatest width of type, exclusive of parapodia, 3.2 mm. Locality. Peru: 111 miles N. W. of Aguja Point. Sta. 4651 (lat. 5° 42' S., long. 83° W.) . Depth 2,222 fms. Bottom of fine, sticky, grey mud. Bot- tom temp. 34.4° F. Several specimens, all incomplete. 11 November, 1904. Oenone Savigny. Descript. Egypte. Hist, nat., 1809 [ = 1822], 1, pt. 3, p. 14, 5.5; Ehlebs, Borgtenwiirmpr, 1868, p. 4o7; Grube, Jahresb. Schlesch. gesellsch., 1879, 56, p. 83; Auoeneu, Fauna Sudw.-Austr. Polych. 1, 1913, 4, p. 290. OENONE TELURA. 335 Aglaura Savigny, Op. cil., p. 13, 54. Andromache Kinberg, Ofvcrs. K. vet. akad. Fc'.rh., 1865, no. 4, p. 571. Aglaurides Ehleks, Borstenwiiriner, 1868, p. 407, 408; Grobe, Jahrcsb. Schlcsch. gesellsch., 1879, 56, p. 83. OeNONE TELURA, Sp. IIOV.'- Plate 62, fig. 2-5. The color of the type at present is a brownish grey, appearing to have been partially bleached in preservation. The body is comparatively short, widest in the middle region and narrowing at the ends, the caudal region being the more slender. The body is strongly arched dorsally and much more weakly convex ventrally. The neural furrow is but slightly indicated. The length is about 60 mm., the body, however, being in a strongly contracted condition, apparently from having been dry at some time. The greatest width, exclusive of parapodia, is 3 mm. The total number of somites is in the neighborhood of 208. The prostomium in outline as viewed from above is subsemicircular, but evidently longer than wide. It is flattened dorsoventrally, and is deeper pos- teriorly than anteriorly. The surface appears to have been wholly smooth, a certain present wrinkling being apparently due to shrinkage, and it lacks all trace of appendages. The eyes are covered in the type. The lateral ones are very much the larger, and are elhptic and somewhat oblique. (Plate 62, fig. 3). There are, following the prostomium, one complete achaetous and non- parapodia-bearing somite and one somite incomplete above. The relations of these two somites to each other seem to be as follows : the second one is oblit- erated above and laterally, but is distinct and sharply limited by deep furrows ventrally, where it appears like the corresponding region of succeeding normal somites; the first somite is much longer and is similaily decidedly longer than the third somite, but shorter than the third and fourth together; it is weakly divided dorsally by a transverse furrow, the two divisions equal, is wholly smooth on the sides, and is ventrally again divided by a transverse furrow that lies much nearer to the caudal margin than to the anterior margin, the anterior division being carried conspicuously forward as a lower lip. The anterior margin of the lower lip is straight. The lateral margin of the somite on each side is a little concave and the dorsal margin is straight. (Plate 62, fig. 3). The ordinary nietastomial somites are very short and closely crowded. ' TTjXoi'pos, remote. 336 THE ANNELIDA POLYCHAETA. They are highly arched above and flattened beneath, with no distinct neural furrow. They are entire or may show above a vague transverse furrow, and are smooth excepting for a few weak longitudinal sulci. (Plate 62, fig. 3). The pygidium is comparatively very small, and bears four, foUaceous, dis- tally narrowed cirri. Parapodia, inclusive of processes, mostly about one fourth the width of the body. Uniramous. Neiu-opodium cylindrical, produced at the distal end into two flattened lobes, one postsetal and one presetal. The presetal is short and distally evenly rounded; the postsetal lobe is much longer, and is distally moderately narrowed and is also convexly rounded. The notocirrus, attached to a short cirrophore near the base of the foot above, has the style narrow at base and then expanded into a conspicuous foUaceous blade which is oblong or oblong-lanceo- late in outline, with the distal end usually convexly rounded, or in some (more caudal ones) subacutely narrowed. (Plate 62, fig. 4). The setae are arranged in a subvertical hne extending in the crevice between the presetal and postsetal hps and proximad of these on the ventral side. They are of two types. The more delicate, colorless, and transparent capillary setae form the upper part of the series and are much the more numerous. They increase typically in length dorsad. Each is flattened and narrows distad to a very fine tip, and is curved or somewhat angularly bent near, or distad of, the exposed part. The ventral setae, which are of the crochet-type, and ordinarily two in number, are similarly colorless and transparent. They are shorter and much stouter. Toward the distal end each narrows to a cervix at which it bends somewhat dorsad and bears two short, obtuse teeth of which the proximal one is decidedly the larger and is ordinarily weakly bifid, with the upper denticu- lation the smaller. The membranous guards are equal. They scarcely exceed the teeth, and then- distal edge is straight and a httle obhque. (Plate 62, fig. 5). The aciculum is stouter proximally than a crochet; it has a very weak double curve and its acute distal end projects slightly from the surface. The mandibles and maxillae are black. The mandibles have stems which are short, acute caudad, and widen clavately cephalad. At the distal end each bears a masticatory plate which is shortly oblanceolate in form; toward the distal end the mesal edge of each presents a weak reentrant angle, and there are a few small weak undulations, or teeth, near this and on the distal edge. There are five pairs of maxillae. Of these the fifth are in the form of simple curved hooks. The fourth are dentate plates presenting at the distal end a longer hook and proximad of this five stout teeth on the right side and four OENONE TELURA. 337 on the left. Each third maxilla has distally a very stout, curved claw and, proxi- mad of that, five small teeth. Each second maxilla has an arm extending along the mesal side of maxilla I and a shorter, distally blunt, arm extending down the ectal side; along the mesal arm is a series of stout teeth of which the next to the most anterior is a long, stout hook much exceechng the others in size; on the right plate is a total of eleven or twelve teeth, and on the left but seven, the teeth in each case extending to the proximal end of the inner branch, which is much shorter on the left plate. The carriers of the first maxillae are produced caudad as exceedingly long and slender, tendon-Uke processes which bend abruptly mesad and unite at the caudal end; at the anterior end each widens into a tri- angular plate with base cephalad; behind each of these anterior plates the car- rier is concavely excised, as usual, and bears a forwardly directed process or tooth. Each of the maxillary plates is extended ectad into a thin process, that of the right being the larger and more conspicuous. The right plate proper is small, scarcely larger than its clavate ectal process, and bears along its mesal border a series of six teeth, with at the distal end a seventh, somewhat larger, hooked tooth. The left plate is much larger, being extended cephalad into a stout smooth hook, and bearing along the mesal edge proximad of this a series of three teeth followed by a long smooth raised edge or ridge. (Plate 62, fig. 2). Locality. Marshall Islands. 12 fms. January, 1900. One specimen which came up on the anchor of the Albatross. This species in general structure and appearance is close to 0. lucida Savigny, type-species of the genus. It presents no trace of obscure antennal nodules indicated in some specimens of lucida, but apparently subject to retraction like true nuchal organs. The maxillae are very similar to those of 0. lucida (0. diphyllidia Schmarda) as figured by Ehlers (Mem. M. C. Z., 1887, 15, pi. 34, fig. 6) and by WUley (Ceylon pearl oyster fisheries report, 1905, pt. 4, pi. 5, fig. 107) and as exhibited in West Indian specimens, but differ in various details. In maxilla II the great fang is the one next to the most anterior one instead of the most anterior; the third right maxilla has but five teeth, exclusive of the large fang, instead of seven or eight, though five may occur in some specimens of lucida, and is in this regard the same as the left one instead of having more numerous teeth. The left maxilla I has but three teeth and a smooth ridge in- stead of eight teeth. The ectal process of the plate of I is differently shaped. Each mandible does not project angularly ectad at its distal end on the outer side as figured for lucida. The crochets of lucida do not show the same inequality in the terminal teeth, with the larger one bifid. A most striking and important 338 THE ANNELIDA POLYCHAETA. difference between the two species is in the relationship ventrally between the two achaetous somites. In lucida the second one projects broadly forward to the border of the mouth, thus completely dividing the first one, whereas in telura the second annulus is separated from the first by a deep transverse furrow. It thus diverges not only from species of Oenone, but Ukewise from those of Lumbrinereis, etc., in which the first annulus is similarly ventrally separated by the forward protrusion of the second. The lower hp is carried clearly for- ward farther than in lucida. The latter species, according to Augener's inter- pretation, is extremely widespread. He beheves it to include the following: — Oenone diphyllidia Schmarda, Oenone pacifica Fischh, and Aglaurides erythraensis Gravier; also possibly Danymene fouensis Kinberg.' He makes the genus, in fact, monotypic; but I am convinced that the form above must be held to be different unless the variability in maxillae II, of the crochets, and especially in the relation of the first somites, are much greater than is indicated by present evidence. DORVILLEIDAE. In these anneHds the body is composed of but a moderate number of somites and is slender and cylindrical in shape, or sometimes fusiform. The prostomium is distinct and is rounded, horseshoe-shaped to quadrangu- lar and pentagonal in outline. It bears a pair of palpi, one pair of articulated tentacles, or else four smiilar, nonarticulated appendages. Eyes four. Nuchal organs primitive, open, ciliated surfaces. The first two somites lack appendages. The parapodia are structurally biramous, though in appearance uniramous, having ventral cirrus and dorsal cirrus with a basal joint or cirrophore supported by an aciculum. The dorsal fascia of the parapodia consists of simple setae, the ventral of composite ones. The pygidium bears either two or four anal cirri, when four are present two being shorter than the others. The proboscis armed with a pair of mandibles and numerous maxillae in two series. Swarming at the surface of the ocean similar to that occurring in the Palolo worms, mentioned under the Leodicidae, is known in the family and has been described in detail for Dorvillea gregarica} ' C/. Augener, Fauna Sfidw.-Austr. Polych. 1, 1913, 4, p. 290. 2 C}. Mayer, BuU. M. C. Z., 1900, 36, p. 1. DORVILLEA CRASSA. 339 These forms occur mostly between tide-marks, and are connnonly found under stones, or in but shallow water. In their alimentary canals have been found such debris as sand, diatoms, spicules of sponges and fragments of crusta- ceans. The forms observed appear to be comparatively hardy in captivity. Some have been seen to swim freely {e.g., D. rudolphi and D. kefersteini, fide Eisig and Mcintosh) \\'ith a wriggling motion, or to crawl about actively. Ophryo- trocha p2ierilis has been found in the body-cavity of Cucumaria plance at Naples by Monticelli (Monit. zool. Ital., 1892, 3, p. 250). Key to Genera. a. With two articulated or moniliform tentacles and two palpi Doriiillea Parfitt. aa. With four similarly formed tentacles, or processes, wliich are simple and non-articulated. Ophrijotrocha Claparide and Mejznikow. Synonymy of Genera. Staurocephalus Grube (1855) has long been used for the more important genus of this family, as has Staurocephalidae for the family; but unfortunately Staurocephalus was previously used in Crustacea (1846). Dorvillea Parfitt (1866, type D. lobata = Staurocephalus rubrovittatus Grube) is the next name apphcable to the genus. This differs in spelling from Dorvilha, applied by Leach to a lepidopterous genus in 1815, and must therefore stand as a distinct name. Paractius Levinsen (1879) is here included under Ophryotrocha Claparede (0. puerilis Claparede and Mecznikow, the type of the latter being, in fact, possibly the same as P. littoralis Levinsen, the type of the first), — as is also Stauroceps Verrill (1900), proposed as a subgenus of Stauronereis. Dorvillea Parfitt. Zoologist, 1866, ser. 2, 1, p. 113. Staurocephalus Grube, Arehiv. naturg., 1855, 21, p. 97. Anisoceras Grube, Vid. meddel., 1856, p. 60. Prionognathus Iveferstein, Zeitschr. wiss. zool., 1862, 12, p. 99. Stauronereis Verrill, Trans. Conn. acad. sci., 1900, 10, p. 647. Teleonereis Verrill, Ibid., 1900, 10, p. 648. Dorvillea crassa, sp. nov.' Plate 62, fig. 6, 7; Plate 63, fig. 1. The general color is duU brown, with the parapodia scarcely paler. No markings. ' crassus, stout. 340 THE ANNELIDA POLYCHAETA. The type is incomplete posteriorly. The part present consists of fifty-one somites. It is 26 mm. long and has a maximum width, exclusive of the para- podia, of 3.4 mm., and inclusive of the parapodia, of nearly 5 mm. The body is widest at and immediately caudad of about the eighth somite. Cephalad of this the body is rounded, somewhat like the frustrum of a cone with the truncate end narrow. Caudad the body narrows continuously and much more gradually. The principal portion of the prostomimn in outhne as seen from above is semicircular, the anterior margin being strongly convexly rounded. It is deep dorsoventrally, with the ventral portion much narrower than the dorsal. There is a very large, circular, black ocular area, or eye, on each side just in front of the posterior paired tentacle, the diameter of which it exceeds, and a much smaller, longitudinally elUptic eye just mesad of each posterior paired tentacle. On the ventral side are two thick, somewhat conical, bodies extending from the bases of the palpi caudad to the mouth; they are contiguous and are distaUy free as conical projections. Two pans of distinct appendages are present in the type. Each of the anterior pair, ordinarily interpreted as palpi, is attached on the ventral surface in the angle between the ventral lobes above mentioned and the ventral projection of the prostomium. The two palpi are separated by less than their diameter, being unusually tliick. Each tapers strongly distad and is at present transversely wrinkled, or jointed, so as to appear to consist of rather numerous short articles and a distinct terminal lobe such as present in various other species. The tentacles, which are of about the same length as the palpi, are much less stout and are cyUndrical. Each is set deeply in an excava- tion in the caudolateral region of the prostomium and extends dorsad. Each is attenuated, but more gradually so than the palpi, and is strongly transversely wrinkled or jointed, the joints numerous. At present they extend only to the fifth somite but appear to have contracted considerably in preservation. A nuchal tubercle shows in the median hne above under the projecting border of the peristomium. The peristomium is about equal in length to the prostomium and is much longer than the second somite. On each side it presents a lobe anteriorly partly separated off above and below by a sulcus, this lobe abutting dorsaUy against the posterior paired tentacle and in front against the anterior paired appendage. On the ventral side it is- deeply excavated semicu'cularly, leaving the portion caudad of the mouth as a narrow band. The border caudad and laterad of the mouth strongly radially furrowed or wrinkled. DORMLLEA ("RASSA. 341 The second somite wholly lacks tentacular cirri or other appendages, like the peristomium. It is of uniform length above and laterally, but is shorter ventrally. The other metastomial somites bear parapodia. The third somite is shorter than the second, the following ones decreasing to the fifth or sixth, with those from this to the twelfth veiy short, after which a length greater than that of the second somite is rapidly attained and maintained with httle variation to the end of the fragment (fifty first somite). The region of very short somites {i.e., the fifth to twelfth) is the deepest part of the body as well as somewhat the widest. AU metastomial somites are strongly convexly arched above and are flattened ventrally. There is a well-marked neural fiurow along the venter, this deepening caudad. The most anterior parapodia agree essentially with the others excepting in being shorter. A tjisical parapodium from the anterior region is strictly uniramous. It is more or less flattened in the cephalocaudal direction, is deeper proxunally than distally, and at the distal end bears two thin, distally rounded, flaps extending entkely across the end of the parapodimn, but not high. These are the postsetal and presetal lobes and are essentially equal in size and alike in form. Caudad these lobes become gradually lower and lower. All para- podia bear neurocirri. Each nem-ocu'rus is attached on the ventral side at the base of the neuropodium. It is thick proximally, tapers conically, and nearly attains the end of the neuropodium. All parapodia also bear notocirri. Each of these is attached above at the extreme base. It is exceptionally stout, tapers conically to an acute point, and in length conspicuously exceeds the parapodium. Some of the notocirri are considerably flattened and all appear to have a large axial blood-vessel. In each parapodium there is a single stout aciculiun, which is colorless, or in some cases shghtly yellowish. Each is curved proximad of the middle, with the concavity ventrad. The apex is acute, but not especially fine. On the dorsal side of the aciculum in a typical parapodium there is a fascicle of simple, strongly flattened, setae, each of which is apically bidentate and has a mem- branous shield over the teeth. (Plate 62, fig. 7). Along one edge these setae are finely serrate, the teeth or scales short. The setae on the ventral side of the aciculum are much more numerous and form a more extended fascicle. They are coarser than the dorsal ones and are all compound. In these the shaft enlarges clavately from point of emergence distad to a httle proximad of its distal end, then again narrowing shghtly to the obhque margin of the socket. 342 THE ANNELIDA POLYCHAETA. The distal portion of the edge of the shaft on the side of the acute distal angle is finely dentate. The distal piece in the compound setae is moderately long, more slender than the shaft, and of uniform diameter until the hooded distal region is reached, where it narrows as usual ; there are two teeth, the distal one much the larger and strongly cui^ved, the subapical one small, acute, and pro- jecting at right angles to the general axis; the guards distally rounded, not rising above the level of the distal tooth. (Plate 63, fig. 1). The mandibles are large and sohdly black throughout. The two pieces are narrowly connected at the level of the proximal ends of the masticatory plates. Each masticatory branch diverges widely from the other one; they enlarge ectad, with the distal margin curving convexly and extending almost directly ectad at the distal portion; the margin is smooth over its proximal portion, toward the middle becoming wavy, and over the distal portion strongly dentate; the most distal teeth are long, curving a Uttle mesad. The shafts are widely separated. Each is of nearly uniform diameter caudad to a little behind its middle, where they expand a little, and then narrow to the acutely pointed caudal end; each shaft is bowed moderately ectad, the caudal ends of the two bending in towards each other. (Plate 62, fig. 6). The numerous small maxiUae form two long articu- lating series on each side, the two series being in contact anteriorly and caudally. Each maxilla bears a single long, simple, curved hook. The maxillae and hooks are longest in the middle region of the series, those of each series decreasing gradually toward the ends. At the proximal end each inner series is continued by a smooth, unsegmented, tendon-Uke, chitinous piece, which is slenderly acute at its proximal end. Each outer series is proximally continued in a similar way by a wider, smooth, chitinous piece which expands caudad, bends more or less into a vertical position, and unites with the one of the opposite series to form a V-shaped piece. Locality. Marshall Islands. Came up on the anchor from a depth of 12 fms. 1899-1900 Exped. One specimen. This species is in the group having a distinct terminal piece to the palpi. In the numerous articles in the tentacles it resembles the New Zealand species, D. incerta (Schmarda) (D. australis Haswell). From that species, however, it differs in numerous details. Unlike incerta, its notocirri do not have terminal articles. The preocular area of the prostomium is shorter than in that species and the anterior eyes, a very striking feature of the species, are much larger, The notocirri are longer. An important difference is in the presence of the conspicuous lobes at the end of the parapodia, these being absent in incerta or GLYCERIDAE. 343 the postsetal lip being but weakly indicated. D. australiensis (Mcintosh) differs from the present species in having the palpi much shorter relatively to the tentacles, and in the greater length and more numerous articles of the latter, the form and proportions of palpi and tentacles in this species much suggesting those of D. filicornis (Grube) from Singapore ; the anterior margin of the man- dibles are smooth or nearly so, lacking the conspicuous, hook-like, teeth of crassa; in the form of the maxillae, the hooks of which are proximally toothed; in having a distinct terminal joint to the notocirri; and in the detailed structure of the setae. D. brevispinis (Grube) from Singapore is a much smaller species than crassa and has distinct terminal joints to the notocirri. D. crassa agrees with D. australiensis and, among others, with D. rubrovittata (Grube) (erucaeformis (Malmgren)) in having a conspicuous, median dorsal, nuchal papilla. Glyceridae. In this family the body is elongate, cylindrical and often slender, tapered at the ends, and is composed of numerous somites. The coloration is not con- spicuous, being pale and uniform. Species often appear reddish because the blood shows through the integument, this being colored red by large coelomic corpuscles which contain haemoglobin. The prostomium is in the form of an elongate cone, which is strongly annu- lated and bears at or near its apex four small tentacles. The basal ring is much longer than the others. Eyes may be either present or absent. A retractile nuchal organ, sometimes spoken of as a "palpus," occurs on each side at the base of the prostomium. The somites in general are composed of two or more annuli. The parapodia are all of one form throughout the body, and either unu-amous or bkamous. Notopodial setae, when present, are simple, typically narrowly limbate and marginally serrate. The neuropodial setae are composite, with the distal append- age acutely tipped and serrate along the edge. Branchiae may be either present or absent; when present either sunple or branched (bifurcate). Nephridia with inner end closed and in connection with groups of soleno- cytes. The proboscis is a strongly muscular and protrusible organ which is glandu- lar at its base and is armed normally with four similar chitinous hooks, or jaws, and bears distally eighteen papillae, of which one is middorsal and one mid- 344 THE ANNELIDA POLYCHAETA. ventral in position. The glands seem to be toxic to certain organisms preyed upon. It is now established that epitoky occurs in this family, certain forms, at least, acquiring at the time of sexual maturity long, natatory, notopodial setae similar to those acquired in various other epitokous forms, the parapodia elongating at the same time. Also with the development of the sexual products the musculature undergoes reduction, the proboscis degenerates, and its jaws may become detached and disappear. At this period of sexual maturity the animals, of course, become pelagic, as is so frequently the case in other forms of similar mode of Ufe.' A very interesting case of epitoky occurs in the new genus Telake (p. 345). The glycerids frequent especially sandy mud at moderate depths. Some- times they are cast up on the shore at beaches, and also at times are found under stones and in the fissures of rocks between tide-marks. They have been ckedged mostly at depths ranging from three or four to a hundred fathoms. Glycera capitata Oersted was dredged by the Porcupine at 664 fathoms ; and the Alba- tross dredged Hemipodus mexicanus, sp. nov., at 628 fathoms, Glycera pro- fundi, sp. nov., at 859 fathoms; while G. brachiopoda Moore has been taken at from 222 to 1,400 fathoms. These cases, however, are exceptional. Many of the glycerids are active animals which progress through the water mth a screw-like motion, probaljly much the same as that they execute in moving in wet sand. In burrowing in the sand they are seen to apply the snout to the surface, then thrusting out the proboscis forcibly and rapidly, and moving step by step into the successive depressions thus made, in the same manner as occurs in Nepthys. Key to Genera. a. Body of the pelagic form presenting two shari:)ly distinct regions, in tlie posterior of which only simple setae occur Telake, gen. nov. aa. No such division with parapodia of posterior region bearing only simple setae. b. Parapodia uniramous Hemipodvs Quatrefages. 6b. Parapodia biramous. c. Proboscis short; supporting piece of maxilla rod-shaped Glycerella Arwidsson. cc. Proboscis long; supporting piece of maxilla triangular or bifurcate. d. Proboscis without hard, dentate processes among softer papillae Glycera Savigny. dd. Proboscis with numerous toothed or hooked pieces among softer papillae. Hemiglycera Ehlers. Synonyrny of Genera. Kinberg (Ofvers. K. vet. akad. Forh., 1865, no. 4, p. 245) transcribes the "Hemipode" used by Quatrefages in his note on Classification of annelids in ' Cf. Arwidsson, Bih. K. svenska vet. akad. Handb., 1897, 23, no. G, p. 30. Also Gravier, Nouv. arch. Mus. hist, nat., 1906, ser. 4,^8, p. 135. TELAKE. 345 the Compt. rendus, 27 March, 1865, as Heinipodia. Quatrefages's name was not properly established in this place, however, since he mentions no species in connection with it and does not give a Latin form. Ehlers (Nach. K. gesellsch. wiss. Gottingen. Math. phys. klasse, 1897, p. 81) also follows Kinberg in using Hemipodia. Quatrefages himself, however, in his Hist. nat. anneles gives the usual form, Hemipodus, in the place where the genus is first really estabhshed, unless perchance Ivinberg's paper appeared before the Anneles, in which case Hemipodia must be used. Telake, gen. nov. Body of medium size, cylindrical, and slender, tapered at the ends. Prostomium long and pointed, the length much exceeding the breadth. Bearing at the tip four small tubercles. Eyes none in the adult. Metastomial somites all two-ringed. Parapodia all biramous, but of two types as regards size and details of development, and particularly as regards the setae, an anterior group bearing composite and limbate setae in neuropodium and notopodium respectively, and a posterior larger group, bearing only simple non-limbate setae. Each branch of the parapodium bears a single ligula, presetal in position. Branchiae none. Notocirri present, reduced, nodular in form. Ventral cirrus short, conical to narrowly plate-like. Genotype. — T. epipolasis, sp. nov. This genus is apparently clearly separated in the character of the para- podia and in the form and distribution of the setae. It resembles ordinary forms of Goniada in having two regions of the body sharply marked off by the character of their parapodia and setae; but differs strongly in having the para- podia of the anterior division biramous and in wholly lacking composite setae in the parapodia of the posterior division. It is, however, probably much nearer to Glycera, which genus has a few species (such as G. capitata Oersted, G. con- voluta and G. minuta Czerniawsky) showing epitokous phases in which the individuals swmi at the surface. All of these surface-forms were taken at night, as in the case of the present one. The nocturnal habits doubtless account for the rarity of their capture. In the epitokous forms of Glycera there seems to be an appearance of simple setae among the composite neuropodials ; but in no case, so far as I can find, is there a division of the body into two regions hke those of the Heteronereis phase of the Nereidae and a complete lack in the poste- rior region of all composite setae. In fact, the change from ordinaiy atokous 346 THE ANNELIDA POLYCHAETA. phase seems comparatively slight. Hence it is felt necessary to separate the new form as the representative of a distinct genus. The character of the arma- ture of the normal proboscis must probably remain uncertain until the atokous form is discovered, as the epitokous forms commonly lose the jaws, while the proboscis itself undergoes reduction.^ Telake epipolasis, sp. nov.^ Plate 63, fig. 4-8; Plate 64, fig. 1. Epitokous Female. The type-specimen has the body-wall colorless and translucent, the viscera showing thi-ough giving a shghtly brownish tinge.' The body is cyhnch'ical; it is widest near the middle of the type-piece, which would be in front of the middle of a complete specimen, narrowing both ways, the prostomium forming a slenderly pointed anterior extremity. The pos- terior region of the type is broken off. The type as at present is 23 mm. long, with a maximum width, exclusive of parapodia, of 1.7 mm. The incomplete type consists of sixty-seven somites. The prostomium continues smoothly the outhne of the peristomium and narrows distad to an acute tip, as usual, having a slenderly conical form. It is fused with the peristomium. The prostomium is three times as long as wide at the base. The rings of the prostomium are too vaguely indicated to be counted with any degree of certainty. The type at present shows on the dorsal surface of the prostomium a median longitudinal furrow which reaches neither anterior nor posterior end. On each side there is also a longitudinal furrow extending caudad as far as the rather conspicuous nuchal organ. A ventral sulcus is rather vague and narrow. The tentacles have the usual position and relations at the tip of the prostomium. The dorsal are decidedly longer and stouter than the ventral, the latter being clearly shorter than the diameter of the end of the prostomium. There are no eyes evident. A palpal lobe, low and but sUghtly differentiated and immobile, lies on each side of the mouth. The peristomium is fused to the prostomium, and ventrally apparently also wdth the succeeding somite to form a prominent broad hp, wliich is crossed radi- ally by numerous fine sulci. The metastomial somites are clearly defined, cylindrical, smooth. Each is ' Cf. Arwidsson, Bergens mus. aarbog, 1908, no, 11, p. 7. - ciri?r6Xa<7is, lying on or rising to the surface. TELAKE EPIPOLASIS. 347 biannulate, the dividing annular surface ordinarily very distinct. The somites increase in length to the region from the fortieth to the fiftieth somites. The last somite of the anterior division (the thirty second) is four times wider than long. As usual, the somites in the more posterior region are a little depressed as compared with the anterior ones. The body is divided into two regions according to the character of the parapodia, these being smaller and with much fewer setae from the thirty second somite, inclusive forward, and larger and with longer and more nimierous setae from that point caudad. The change takes place abniptly. The parapodia of the anterior region are bifid distally, with slight neuropodial and notopodial lobes which are equal and very similar. In comparison with the width of the body the parapodia are veiy short and slender, thicker dorsoventrally than anteroposteriorly. Each bears two long presetal lobes, or ligulae, one on each branch, of which the notopodial is the longer. There are no distinct postsetal Ups. The neurocirri are attached distad of the middle of the parapodia. Each is broadly united with the neuropodium at its base and is conicaUy narrowed distad, falling short of attaining the end of the neuropodium. The notocirri are attached on the side of the somite, well above the base of the neuropodia. Each is a small nodular body constricted at the attachment and shortly sub- conically pointed distad. (Plate 63, fig. 4). The anterior pairs of parapodia decrease in length decidedly cephalad, the first two or three pairs in particular being much reduced. The parapodia of the posterior, or sexual, division of the body are similar in general structure to those of the anterior, but are decidedly broader in the dorsoventral direction, proportionately much more flattened in the cephalo- caudal direction, and, as mentioned, have more niunerous and somewhat longer, more widely spreading, setae. In a typical parapodium of this region, as for example the thirty seventh, the depth at the base is great and decreases decidedly distad. The hgulae are larger and more foUaceous, each broad at base and narrowed to an acute tip, and extended as a narrow band some distance along the dorsal edge of the notopodium, or the ventral of the neiu"opodivmi, as the case may be. The two ligulae are subequal, or the nem-opodia may be somewhat larger. On the dorsal side there is a tliin vertical membrane running as a narrow convex band proximad to the base of the notopodium, and distad more narrowly about the end caudad of the setae. Above this at the base is the notocirrus, which is in the form of a very small rounded nodule. Along the ventral edge of the neuropodium is attached the neurocLrrus. This is somewhat foUaceous 348 THE ANNELIDA P0LYCHAP:TA. and is attached along one entire edge, only the acute distal tip being free, this projecting distoventrad at the edge of the hgula. (Plate 63, fig. 5). In a typical parapodium of the posterior region, as in the thirty seventh, there are two pale transparent acicula, of which the neuropodial is distinctly the stouter. The setae are all simple. They taper distad into fine tips, which are normally curved. The setae are wholly smooth, lacking entkely both lunbi and teeth. They increase in length from the lowermost dorsad in the neuro- podium and in the opposite direction in the notopodium, so that in the series taken together those at the middle are longest, with the others decreasing towards the ends of the series. In the thirty seventh and adjoining parapodia, for example, the neuropodials number mostly from eight to ten, the notopodials six or seven. In the parapodia of the anterior region the notopodial setae are simple Uke those of the posterior region, but shorter and apparently more flexible, being commonly much curved, often in a conspicuously sigmoid manner, and differing more particularly in being narrowly limbate along one side, the limbus finely cross-marked or serrate. (Plate 63, fig. 6). The neuropodial setae of the anterior division are composite. The shaft ends distally in a socket of inter- mediate type, one edge rising considerably higher than the opposite one. The end-piece is long and varies much in size. It has a finely pointed, curved tip and is narrowly limbate along one side, the Umbus being finely cross-striate, or vaguely serrate, as in those of the notopodial setae. (Plate 64, fig. 1). There are thus three distinctly marked types of setae, two represented in the notopodia and neiu-opodia respectively of the anterior parapodia, and one represented in the parapodia of the posterior division. (Plate 63, fig. 7). The proboscis is wholly retracted, and, as it is thought best not to dissect the single specimen at this time the armature is not described, — and it is likely to have been lost under any conditions. Locality. Gilbert Islands: off Ai-hno reef. Taken at surface by night light. One male. 24 January, 1900. This form has colorless, semitransparent tissues similar to those of most other pelagic annelids. The uniformity in the characters of the simple setae of the posterior region, with the contrasting character between notopodials and neuropodials of the anterior region, are, perhaps, the most distinctive of the outer structural features. Hemipodus Quatrefages. Hist. nat. annelos, 1865, 2, p. 194; Arwidsson, Bergens mus. aarsbog, 190S, no. 11, p. 27. Hcmipodia Kinberg, Ofver K. vet. akad. Forh., 1865, no. 4, p. 245. HEMIPODUS MEXICANUS. 349 HeMIPODXJS MEXICANUS, Sp. IIOV. Plate 63, fig. 2, 3. The general color at present is dusky grey-brown, with a somewhat darker niiddorsal line evident in parts. The parapodia are lighter, more yellowish, and the setae are colorless. The type is incomplete caudally. In its present condition it is about 29 mm. long and counts nearly fifty-five somites, the precise number not being determinable because of the worn and frayed condition of the posterior region. The greatest width, which is a httle in front of the middle of the fragment, is 2.8 mm. From this region the body narrows conspicuously both cephalad and caudad, the posterior narrow region being more slender and longer. The prostomium has its base sunk into the anterior end of the body, than which it is very much more slender. It is slenderly conical, with the distal end curving somewhat ventrad. Because of the insinking of the head in the type the precise number of annuli cannot be satisfactorily determined, but it seems to be eight or more. The tentacles are colorless and small, much less than the median diameter of the prostomium. The somites are strongly convex both dorsally and ventrally, the transverse diameter not much exceeding the dorsoventral one. There is no distinct neural groove, though slight furrows set off a midventral neural region. All somites, at least of the anterior and median regions, distinctly three-ringed. The parapodia at the anterior end are situated clearly below the middle level of the sides, rising higher caudad. The first two pairs in the type are directed forwards, the others sublaterad. Parapodia are uniramous, short, and subcylindrical. Each at the distal end with two presetal ligulae, these slen- derly cylindroconical, long, contiguous at base, with the dorsal one a little longer than the ventral. The postsetal Hgula is single, proximally broad, but much shorter than the presetal ones. The neurocirrus is situated on the ventral sur- face near the middle of the parapodium in the anterior ones, further proximad caudad; it is conically pointed and short, in no case exceeding the tip of the postsetal process and in most falling clearly short of attaining this. The dorsal cirri are situated on the side of the somites considerably above the bases of the parapodia; they are very small cylindrical tubercles, almost abortive. (Plate 63, fig. 2). The setae are mostly compound. The shafts of these are slender, with the 350 THE ANNELIDA POLYCHAETA. sockets moderately enlarged, intermediate in type, though in some asymmetry may be considerable. In these the blade is long and slenderly acuminate, with the tip long and fine, and bears along one side a series of long fine scales or teeth, which are usually closely arranged but in some appear farther apart. (Plate 63, fig. 3). A few sunple setae occur in some of the fascicles but could not be detected in others. They are long, with finely acute tips, and are obscurely minutely roughened. The proboscis is wholly retracted. Locality. Gulf of California: Sta. 3437 (lat. 27° 39' 40" N., long. 111° 0' 30" W.). Depth 628 fms. Bottom of brown mud with black specks. Bottom temp. 40° F. 23 April, 1891. One specimen. Among other features characterized by the abortive notocirri and the two long, subcylindrical, presetal ligulae of the parapodia. Glycera Savigny. Descript. Egypte. Hist, nat., 1809 [ = 1822], 1, pt. 3, p. 12, 36. Rhynchoholua CLAPARfeDE, Annolides Ch^top. Golfe Naples, 1868, p. 182. Euglycera Verrill, Trans. Conn. acad. sci., 1882, 4, p. 287. Glycera Akwidsson, Bergens mus. aarbog, 1908, no. 11, p. 5; McIntosh, British annelids, 1910, 2, pt. 2, p. 477. Glycera dibranchiata Ehlers. Borstenwiimier, 1868, p. 670, pi. 24, fig. 1, 3-8, 10-28. Rhynchobolus dibranchiatus Verrill, Invert. Vineyard Sound, 1873, p. 596, pi. 10, f. 45, 46; Amer. journ. sci., 1874, ser. 3, 7, p. 132; Proc. Amer. assoc. adv. sci., 1874, p. 370, 373; Webster, Rept. N. Y. state mus., 1879, 32, p. 17. Euglycera dibranchiata, Verrill, Trans. Conn. acad. sci., 1882, 4, p. 287; Webster & Benedict, Rept. U. S. Comm. fish., 1885, p. 726. Locality. Atlantic Coast: Between Cape Hatteras and Nantucket. Sta. 2305 (lat. 35° 23' N., long. 74° 51' 30" W.). Depth 58 fms. Bottom of fine grey and black sand. 21 October, 1884. One complete specimen. Glycera profundi, sp. nov.i Plate 64, fig. 2-6. Color of the preserved type brown, in part of shght reddish cast, the venter with a pale median longitudinal stripe; the parapodia yellow; prostomium yellow at tip. 'profundum, depth. GLYCERA PROFUNDI. 351 The body is widest at about the eighteenth setigerous segment from where it narrows continuously caudad. The body is nearly cylindrical, a little less convex ventrally than dorsally. The greatest width of the type, exclusive of parapodia, is 4.5 mm.; including parapodia and setae, 8.5 mm. The prostomium consists of the usual broad basal portion, which is strongly transversely wrinkled, and the slender subcorneal smooth portion. The basal portion is proportionately short. The conical process is somewhat compressed dorsoventrally, is marked by a distinct median longitudinal furrow both above and below, and is divided transversely into eight or nine rings. (Plate 64, fig. 2). All segments are very short, and the anterior ones especially are closely crowded at widest region, being eight or nine times wider than long. All seg- ments are conspicuously triannulate. The annuli are all equal in length, or, in the anterior region, the median, parapodia-bearing, one of each somite is somewhat wider laterally than the others. The notocirri are inserted on the sides of the body above bases of the para- podia. They are very small, whitish, cylindrical papillae, which are absent from the first two setigerous segments. The first two parapodia, or properly, the neuropodia, are situated high on the body at the sides of the mouth. They are small. The first two parapodia lack neurocirri; they are small and sub- conical, presenting a flattened, distally rounded, apical Up, which is slightly notched but not divided. The immediately succeeding parapodia show a shght, rounded postsetal hp and a large presetal Up divided into a much stouter and shorter, basally thick, ventral division acuminate at tip, and a more slender, pointed dorsal lobe. The neurocu-rus, attached to the middle of the ventral surface and not reacliing the end of the neuropodium by a considerable distance, is present and is thick at base and strongly pointed distally. (Plate 64, fig. 3). In proceeding caudad the parapodia become longer and proportionately more slender and cyUndrical. The dorsal presetal lobe becomes transformed into an unbranched gUl, being thin and elongate, with the foUaceous base reduced in relative size, but not or but Uttle exceeding the ventral division, which becomes of more uniform width and not especially tliickened proximally. The dorsal Ugulate gUl is attached on the dorsal surface near the distal end of the para- podium, and is suberect. The neurocirrus is developed into a ventral gUl similar in structure, appearance, and size to the dorsal one, which does not reach the tip of the postsetal lobe. (Plate 64, fig. 4, 6). Acicula pale yellowish, transparent, two in number, of which the ventral is much the stouter. The setae of the parapodia, excepting first two, as usual, 352 THE ANNELIDA POLYCHAETA. in three groups. Of these the dorsal consists of simple bristles, the others of compound ones of the usual form. The socket of the compound setae is slightly asymmetrical, being deeper toward one side than the other; the blade is moder- ately short, and slenderly acuminate, with the surface and edges apparently wholly smooth. The proboscis in the type is only partly extended, and its detailed structure is not described. The extended portion is about 8 mm. long and 3 mm. thick at distal end. Locality. Gulf of California: Sta. 3435 (lat. 26° 48" N., long. 110° 45' 20" W.). Depth 859 fms. Bottom of brown mud with black specks. One spechnen, of which the caudal end is missing, taken 22 April, 1891. This species in general structure suggests G. branchiopoda Moore which has been recorded at depths varying from 222 to 1,400 fms. at localities from Monterey Bay to the lat. of Cape Calnett, Lower Cahfornia. Both these species occur at depths much greater than usual in the family. G. profundi is a larger and much stouter species, which reaches its maxunum width farther cephalad; the prostomium has nine rings in its distal portion mstead of but seven, and the proportions are apparently considerably different; the caudal ring of the somite is not largest; the first two parapodia differ in lacking any conspicuous, pointed, presetal lobe; the other parapodia also differ in structure and proportions, the neurocirrus, e.g., or ventral gill, of most segments being relatively much shorter, never attaining the end of the parapodium, whereas in branchiopoda it decidedly exceeds it; the dorsal gill is also relatively shorter. The blade of the compound setae appears to lack denticulations, etc. Glycera fundicola, sp. nov. The type, which is caudally incomplete and is in two pieces, is a robust specimen of uniform, Ught yellow color. The prostomial process is broadly conical, being rather wider across base than long, compressed dorsoventrally, the depth being much less than the width. Composed of seven distinct rings. Tentacles slenderly subulate. Anterior somites short and closely crowded as usual, those of the middle and posterior region much longer. All very distinctly biannulate. The parapodia are long, moderately compressed in anterocaudal direction, more strongly so distally. Each at the end presents four lobes, of which the two presetal are long, slenderly conical and almost subulate, equal, while the ARICIIDAE. 353 posterior ones are only slight, broadly rounded lips separated by a shallow emar- gination. Neurocirri attached on ventral surface well distad of middle of para- podium, stout at base, but strongly tapered distad like the presetal lobe, which is a little smaller. The notochi-us is attached on the side of the segment a little above the base of the parapodium. It is a pale, short, subcychndrical, distally rounded papUla. No brancliiae or brancliiform organs are present. On the fifth parapodia the dorsal presetal lobe is scarcely evident, though normally developed on the sixth, while on the anterior four pairs it is quite absent, leavang a single, pointed, presetal lobe. The first two pahs of parapodia much reduced, as usual; both retain the neurocirrus. Acicula two in each parapodium, -ftdth the notopodial the stouter; tapered to rather fine, curving tips; pale. The composite neuropodial setae are char- acterized by their pecuhar sockets; the sides of the socket are long and flare widely apart, the tips curv'ing ectad away from the base of the terminal piece. The eight anterior segments present in the type have a length of 50 mm. Greatest width, exclusive of parapodia, 4 nun. Locality. Pern: 111 miles N. W. of Aguja Point. Sta. 4651 (lat. 5° 42' S., long. 83° W.). Depth 2,222 fms. Bottom of fine sticky gray mud. Bottom temp. 34.5° F. 11 November, 1904. This species appears to come from the greatest depth recorded for a glyc- erid. Aeiciidae. These are typically elongate polychaetes, in which the body is commonly obviously flattened dorsally and convex ventrally; pointed at both ends, but more strongly so caudad. Somites short. Body very fragile. Commonly of a rose-tint. The prostomium is in the form of a cone devoid of processes. Eyes may he either present or absent. Peristomium ^vithout processes, achaetous. ParapocUa normally subdorsal in position; often dorsolateral anteriorly and dorsal in position posteriorly. Biramous. Rows of tubercles on caudal surface of the anterior pairs often present (Aricia). Often dividing the body into two regions by differences in their form and in the character of the setae borne. Setae simple, normally of several types, always including an elongate, distally acute form which is strongly cross-ridged, appearing to be annulated or camer- 354 THE ANNELIDA POLYCHAETA. ated. Stouter, spine-Uke or clavate, camerated forms may also occur, these being in the neuropodia and confined to the anterior region. Branchiae present, these Ugulate in form and dorsal in position. They begin on one of the first twenty somites as rudimentary processes, increasing gradually in size and usually continuing to near the caudal end; often forming two more or less distinct groups. Anal cirri two or four, usually long. Proboscis short, unarmed, distally simply frilled, or sometimes more dis- tinctly digitate, in some not evaginable. Larvae non-pelagic. Otocysts, such as occur, among polychaetous annelids, also in the Areni- colidae, Terebellidae, and SabeUidae, are found in some ariciids. Wlien found in this family they occur on a limited number of the anterior somites. Each is an invagination ordinarily close to the notociri-us. Another type of sense- organ, the more widely occurring "lateral cUiated organs" or "lateral line organs," are located farther ventrad and are to be found in all regions of the body.* Ariciids occur from the littoral zone down to considerable depths. Aricia norvegica Sars was dredged by the Challenger from 1,340 fathoms. They frequent mud, and sand more or less mixed with mud. They five upon small organisms and often ingest much foreign matter, their intestines frequently con- taining sand and debris of shells, Foraminifera, etc. (Gravier, Nouv. arch. Mus. hist, nat., 1908, ser. 4, 10, p. 167). Key to Genera. a. Neuropodium with a laminate, festooned border, opposite ones often joined across the venter. Aricia Audouin and Milne Edwards. aa. Neuropodium not so, simply bifid or entire. 6. Prostomium anteriorly rounded, button-shaped Nainereis Blainville. 66. Prostomium pointed. c. On some somites of the posterior division each branchia with five or more filaments forming a transverse series and leaving only a narrow middorsal region naked; peristomium strongly reduced ventrally Branchethus, gen. nov. cc. Branchiae ligulate, never with simple branches in transverse series; peristomium not reduced ventrally Scoloptos Blainville. Nainereis Blainville. Diet. sci. nat., 1828, 57, p. 491. Naidonereis Malmuren, Annulata Polychaeta, 1867, p. 73; Ehlers, Zeitsch. wiss. zool., 1875, 25, p. 59; McIntosh, Aim. mag. nat. hist., 1905, ser. 7, 15, p. 48. ' For an excellent account of the occurrence and structure of otocysts in polychaetes see P. Fauvel, Recherches sur les Otocystes des Anndlides Polychetcs, Ann. sci. nat., 1907, ser. 9, 6, p. 1-149, 3 plates. NAINEREIS RETUSICEPS. 355 NahiereU Mesnil and Caullerv, Bull, scientif. 1898, 31, p. 143. Nainereis McInto.sh, BritLsh annelids, 1910, 2, pt. 2, p. 516. Theodisca F. Mulleb, Archiv. naturg., 1857, 24, p. 1. Nainereis retusiceps, sp. nov.^ Plate 65, fig. 3-5. The general color is yellow, of a sliglitly brownish cast. The body is moderately long and slender, depressed, but little, convex above and decidedly more strongly arched below, not grooved. At the caudal end the body is flattened, thin and wedge-shaped. It is also somewhat similarly flattened at the anterior end (inclusive of peristomium) . The body is narrow in the region just in front of the middle, from where it widens distinctly both cephalad and caudad. The total length of the type is about 18 mm. and the width in the anterior broad region is 1.9 mm., exclusive of the parapodia, and in the broadest region caudad of the middle, about 2 mm. There are about one hundred and sixty-five very short and closely crowded somites. The prostomium is wide and rather short, anteriorly bluntly rounded. It is flattened dorsoventraUy, deepest at base. There is a shallow median longi- tudinal sulcus above. At the middle of the length there is a shallow transverse furrow which on the sides is deeper, forming conspicuous notches, in each of which the nuchal organ lies. The median longituchnal furrow extends around the anterior end and continues caudad beneath as a wider fm-row extending to the mouth. There are no eyes or appendages. The peristomial region is double, the two rings, wholly achaetous and without appendages, are less strongly separated above but are very distinct laterally and ventraUy. Together they narrow cephalad like the frustrum of a cone. The two together are above shorter than the prostomium and longer than the first setigerous somite, though decidedly less than twice so. On the ventral side the anterior ring is incomplete, each end lying at the lateral border of the mouth, and lying partly in an excavation of the posterior ring, which ex- tends forward between the ends of the anterior one to limit the mouth on its caudal side. This median region of the second ring, the labium, is straight anteriorly and is crossed longitudinally by fine sulci, which at the sides are somewhat obUque. The metastomial somites are all extremely short, in the widest anterior ' retusus, blunt, ceps, head. 356 THE ANNELIDA POLYCHAETA. region (i.e., near sixteenth somite) being sixteen times as wide as long. The anus is terminal and is surrounded by a ring of tubercles; cirri on the ventral side as very short subcorneal processes. The parapodia throughout the length of the body are located high on the sides, near the dorsal level. All the parapodia are distinctly biramous, with the branches well separated. The parapodia vary somewhat in form in different regions. In the anterior region each branch consists of a low, rounded setig- erous eminence with a conspicuous postsetal process. The postsetal process of the notopodium is subconical, more or less flattened in the anteroposterior direction and longitudinally furrowed or concave at base on the setal side; the tip is prolonged and acute. The postsetal process of the neuropodium is similar to that of the notopodium, but is shorter, broader at the base, being prolonged at the base on the ventral side, and is rather more strongly flattened. (Plate 65, fig. 3). In the posterior region the branches of the parapodia proper have become stouter and more elevated, the postsetal process being relatively smaller and more slender and cylindrical, cirriform, often appearing only as short, post- setal points, and the setigerous process proper often pointed and nearly equally elevated. In the anterior region the setae are of two types, both simple. There are the long, conspicuously acuminate and slenderly tipped capillary setae having the characteristic camerated, or grated, structure, with serrated margin. The cameration is absent proximally and over the slender tips. This type is found exclusively in the notopodium, and occm's as well in the neuropodium in a fascia much larger than that of the notopodimn. (Plate 65, fig. 5). Besides these there are in the neuropodium ari-anged commonly in a bow on the ventral side of the circumference of the fascia, a number (often eight or ten) of much stouter, spine-Uke setae. The greater part of each of these is bmied, the free portion being much shorter than that of the capillary setae. The free part is weakly sigmoid, presenting a longer proximal curve with convexity dorsad and a short distal ciirve with convexity ventrad. It narrows distally, the distal end being acute. Each shows a fine, medullary, longitudinal fibrillation and, along the dorsal half only, a transverse ridging, or cameration. (Plate 65, fig. 4). The acicula are stout and colorless. Branchiae begin on the sixth somite. They are situated on the dorsum, each a little mesad of a corresponding notopodium. All are simple, and a single pair is present on each branchiferous somite. They are all flattened in the cephalocaudal direction, and narrow from the base to an acute tip. The first BRAXCHETHIS. 357 few are shorter than the notopodial postsetal process; but they increase m length and breadth in going caudad and in the middle region exceed the postsetal processes. In this region, however, a branchia laid transversely does not wholly attain the base of the branchia of the opposite side. The branchiae continue to the caudal end, but in the caudal region have become much reduced, more conical in form, and smaller than the postsetal processes. The brancliiae in all cases are strictlv entire, none showing any such shght tendency to bifurcate at the tip as noted by Ehlers for Scoloplos cylindrifer. Locality. Paumotu Islands: Rangiroa Island, Mohican Reef. 23 Sep- tember, 1899. One specimen. The form of body in this species is characteristic, widening from a little in front of the middle both cephalad and caudad, somewhat as described for M. longa Moore. From this form, however, it differs decidedly in various other structui'al details, such as the proportionately longer prostomium, in having the peristomiuni clearly shorter than the prostomimn, in having the branchiae begin on somite VI instead of on X to XII, the less filiform branchiae, etc. Branchethus, gen. nov.' Prostomium in the form of a truncate cone with a more flexible process or palpoid on the truncate surface, nearly as in Scoloplos, without eyes or ten- tacles. Peristomium long above, but narrowing strongly ventrad and almost obUt- erated in the midventral region. Proboscis short, and wholly smooth. Body elongate, much broader in anterior third than caudally; strongly flattened above, convex ventrally. Body divided into two regions strictly distinct in the character of the parapodia. In the anterior division the parapodia more lateral in position, with neuropodia much elongated in the dorso ventral direction and bearing very nu- merous, special, stout setae and longer, finer, capillary setae, both of which are strongly annulated, the notopodium bearing setae of the finer tj^pe only. Pos- terior border of neuropodium not festooned, but in the middle region bearing a short, foliaceous, distinctly rounded postsetal flap. Parapodia of the second and major division of the body with neuropodia not elongate dorsoventrally; more slender and proportionately longer, and bearing setae of the long, fine ' /9pd7x'a giUs, fidos, character. 358 THE ANNELIDA POLYCHAETA. kind only. The somites of the first division clearly longer than those of the second. Branchiae beginning on somite VI. The first ones small, simple, and ligu- late. In the posterior part of the anterior division some become two-branched. In the anterior portion of the posterior division the branchia on each side of each somite consisting of a transverse series of five or more long, cyUndrical fila- ments arising contiguously and from a common low base. In the posterior region the branchiae are again simple, one pair on each somite, and much reduced. Genotype. — B. latum, sp. nov. This genus is nearest Scolopos from which it is most readily distinguished by the highly and specially developed condition of the branchiae of the middle region of the body and by the form of the peristomium, which in the second genus is in the form of a truncate cone Avith no such great reduction on the ventral side as occurs in Branchethus. Branchethus latum, sp. nov.' Plate 64, fig. 7-11; Plate 65, fig. 1, 2. The body itself is brown throughout and with no special markings except- ing on the sides of the peristomium, which are blackish or deep purplish. The parapodia are paler, yellowish, and the setae are colorless, or very dilute, trans- parent yellow. The branchiae are more or less tinged Avith purple, the seriate ones of the middle somite appearing darkest, the most posterior ones light- est. The tips of the neuropodia and its processes are in the middle region also in part marked with purphsh. The notopodia are also marked with some distal purplish areas. The postsetal processes of notopodia commonly have a piirphsh spot on basal region, and those of neuropodia above at their bases. The body is very broad anteriorly, the greatest width being attained near the thirteenth somite, from where the body narrows strongly cephalad, and, beginning near the caudal end of anterior division of body, at first strongly and then more gradually caudad, the posterior region becoming rather slender. The dorsum is flat throughout. It shows a clearly impressed, median longi- tudinal furrow. The venter is considerably flattened also in the anterior region, where the depth of the body in proportion to the width is very small, while pos- ' latus, broad. BRANCHETHUS LATUM. 359 teriorly it becomes strongly convex. There is a distinct median longitudinal neural furrow, which becomes more sharply defined in the posterior region. Neither of the tj^pes is complete posteriorly. One, having a total length of 47 mm., retains sixty-four somites. Its maximum width, exclusive of the para- podia, is about 8 mm. The other specimen is 80 mm. long, has a maxunum width of 7.5 nun., and consists at present of nearly 126 somites. In both specimens the first division of the body embraces twenty somites. The prostomium caudaUy is a httle expanded. The main portion of the prostomium is strongly subcorneal, distally tnmcate, the distal surface at present showing a softer rounded eminence, which is probably contracted from a palpoid article such as is present in Scaloplos, the types having been at some time, it appears, partly dry. Relatively to the succeeding region the prostomium is very small, appearing as a mere tubercle on the anterior face. No eyes are present. The peristomium above is much longer than the second somite, with the anterior margm nearly straight. The anterior margin on each side is a little concave and curves obliquely caudad of ventrad, the peristomium then becom- ing narrower and incomplete at the middle of the venter, on each side of the venter ending in an acute angle, the two arms leaving a very obtuse reentrant angle between them which is filled by the soft border of the proboscis. Above on each side at the anterior border is a conspicuous nuchal groove or pit. The proboscis is very short, much broader than long, and is wholly free from papillae, wrinkles, or other unevenness. The first metastomial somite, like the peristomium, narrows conspicu- ously ventrad but less strongly so than the latter. In one specimen, at least, it shows a sUght median incision in the anterior border. The succeeding somites are not narrower ventrally than dorsally. They increase in length to somite V or VI, after which they remain of essentially uniform width to the end of the anterior division of the body. At the widest part of the body the somites are near five and a fourth times wider than long. The segments m the posterior region of the anterior division and the anterior region of the posterior show a tendencj^, particularly above, to be bent angularly a httle forward at the middle, this being more pronounced in one type than in the other. In the posterior division the somites are much shorter, being only from one half to one thud as long as those of the anterior division. They are shortest in a region covering about twelve somites beginning three or five somites behind the anterior end of the division. In the median dorsal region of each somite, in the median groove, there is in 360 THE ANNELIDA POLYCHAETA. each somite of the second division a low, short ridge or rounded elevation on the anterior side of the somite, this often broken into two tubercles, and conmionly purplish in color. In the more posterior somites this ridge is more elongate and lacks any purplish pigment. The parapodia of the anterior division are all strongly developed, with both branches conspicuous. They are reduced in size gradually at the anterior end, but in all cases are large and distinct. The neuropodia are strongly elongate in the dorsoventral direction, the distal end Unear, or linear oblong, in outline, the remaining part increasing strongly in thickness proximad. They decrease in size both ways from near the middle of the series. The caudal distal edge is shghtly raised and, ventrad of its middle, is prolonged into a pointed lobe which is subconical, with thick base, or in the more posterior ones becomes more or less flattened and broader, and in the most anterior ones much more slender. The notopodia of the anterior division are much less stout than the nem'opodia, from which they are separated distally by a deep and wide cleft. Each bears a large and very conspicuous postsetal lobe, wliich is broadly subconical, being proximally as broad as the notopodium proper, and distally prolonged into a slender tip with incurving sides and acute tip. Each postsetal process has a pui'pUsh spot on its middle. In the anterior parapodia of the posterior division the neuropodia are abruptly much smaller than those of the anterior division, being still, however, stouter than the notopodia. Caudad the branches be- come gradually larger and more slender, the neiu'opodia exceeding the notopodia, with the cleft between verj' deep. In the most caudal region of the longer fragment the cleft between the branches becomes very shallow and the noto- podia appear more tubercle-like. The parapodia in this region are much flat- tened in the anteroposterior direction and extend out dorsad and ventrad at the base. No true cirri occur. Nearly all the setae of the posterior division of the body have been lost. Those detected are all of a very fine, long, capillary type, with strongly marked cross-striation, or annulation. Those of the notopodia of the anterior parapodia are of the same type. (Plate 65, fig. 2). In the anterior neuropodia, setae of this type occvir along with numerous setae of a much stouter, shorter, special type, the setae being very numerous and densely arranged in vertical series. The stout, blade-Uke setae all have the free portions strongly curv^ed and acutely tipped; the tip curves shghtly in the reverse direction. The setae are strongly and closely camerated, or cross-striate, like the finer and more flexible capillary setae. (Plate 65, fig. 1). PARAONIDAE. 3G1 The branchiae begin on the sixth somite. The fii-st seven branchiferous somites have each a smgle pair of simple branchia, each of which is inserted on the dorsum nearer to the correspondmg notopodium than to the middorsal line. These branchiae are flattened and are acutely acmiiinate. (Plate 64, fig. 7). Each is purpUsh proximally and less strongly so along each side to near the tip. They increase in length caudad, but in no case when laid transversely do they reach the middorsal Une. The eighth branchiferous somite in both of the type- specimens has a simple branchia on the right side, while that on the left side is double, two equivalent branches arising from an almost obsolete common base. On the ninth and following somites the branchiae each presents two equivalent branches, contiguous or united at the veiy base, as far back as the thirteenth branchiferous sonaite, inclusive, in one specimen and the fifteenth in the other. (Plate 64, fig. 8). In the first case, on the thu-teenth, fourteenth, and fifteenth brancliiferous somites the branchiae have three branches. In the second speci- men, on the last somite of the division (fifteenth branchiferous) the left branchia has three divisions, and the right one foiu*. In the anterior region of the posterior di^dsion of the body the branchiae are much more strongly developed, the num- ber of filaments rising to as many as nine. .\11 the filaments in each lateral group are arranged in a straight transverse series. (Plate 64, fig. 9). The space between the series of opposite sides in aU cases exceeds the length of the series, but the latter is decidedly greater than the distance from the most mesal filament to the middorsal line. The filaments in this region are much longer than in the anterior region. Most filaments are lost; but one at the mesal end of a series was found which reached across to the ectal end of the opposite series. In going farther caudad the number of filaments in each group and their length again decreases. In the most posterior region of the longer type the branchiae have become again all simple, mth a single pair to each somite, these short and without purplish pigment. (Plate 64, fig. 10, 11). Locality. Off Panama: Sta. 3354 (lat. 7° 09' 45" N., long. 80° 50' W.). Depth 322 fms. Bottom of green mud. Bottom temp. 4G° F. 23 February, 1891. Two specimens. Paraonidae. Certain genera, namely Aricidia and its allies, that have commonly been placed under the Ariciidae are more properly to be placed in a separate family, as was first pointed out by Mesnil and Caullery (Bull, sclent., 1898, 31, p. 126). 362 THE ANNELIDA POLYCHAETA. Since Levinsenia Mesnil (1897) has been shown by Cerruti (Mitth. Zool. sta. Neapel, 1909, 19, p. 459-512, pi. 18, 19) to be a synonym of Paraonis Grube (1873), the family name is by that author properly changed to Paraonidae. A conspicuous structiual difference between Ariciidae and Paraonidae lies in the complete lack of cross-ridged, or camerated, setae in the latter. All have a slight sensory papilla at the apex of the prostomium and may or may not have also a tentacle. Aricidiopsis Johnson is synonymous with Aricidia Webster. Key to Genera. a. With no tentacle. 6. With specially modified stouter setae or spines, often as hooded crochets, occurring only in the posterior neuropodia Paraonis Grube. 66. Such modified setae occurring only in the posterior notopodia Paraonides Cerruti. aa. A tentacle present, dorsal in position. 6. Specially modified stout setae or spines occurring only in the posterior neuropodia. Aricidia Webster. 66. Such setae occurring onl}' in the posterior notopodia, these setae acicular in character. Cirrophoriis Ehlers. GONIADIDAE. These are forms of mediimi or large size in which the body is elongate, slender, and somewhat depressed, and is composed of numerous somites. Colors normally weak and uniform; sometimes pinkish from the blood, which, as in the Glyceridae, contains large corpuscles in which haemoglobin is present; some show a different color, such as a greenish tinge, when carrying ripe ova. The prostomium slenderly conical and divided into from seven to eleven annuli, of which the most anterior bears four small tentacles. Eyes either present or absent. Nephridia with inner end closed and with solenocytes. A genital funnel opening into nephridial duct at time of ripening of sex products. Parapodia of anterior region of the body uniramous, those of the middle and posterior regions biramous. Neurocirri conical. Notocirri more or less flattened. Setae of the uniramous parapodia simple. In the biramous parapodia the notopodial setae are simple, the neuropodial composite. Anal cirri two. The proboscis is long. As in the Glyceridae it bears at its distal end a circle of normally cigliteen papillae, of which one Ues in the middorsal and one in the midventral line. The chitinous pieces of the armature are numerous, consisting of few, large hooks, or toothed jaws proper, and more numerous, smaller CHAETOPTERIDAE. 363 horny jaws or paragnatha, each of which is normally composed of two pieces. The jaws are arranged in various series, mostly two to five in number. In distribution and habits very similar to the Glyceridae with which they form a natural and compact group, which I believe it advantageous to designate as a superfamily, the Glyceroidea. Key to Genera. a. An insensible transition from the uniramous parapodia to the biramous; with no chitinous pieces on the sides of the proboscLs Glycinde F. Muller. aa. Two regions of body clearly distinct in the character of their parapodia; chitinous pieces in adults on each side of proboscis, these V-shaped and joined together. Go^iiada Audouin and Milne Edwards. Epicaste Kinberg (1865) and Eone Malmgren (1865) are synonynxs of Glycinde F. Miiller. GoNiADA Audouin and Milne Edwards. Hist. nat. Utt. France. Annelides, 1834, 2, p. 244; Qu.\trefages, Hist. nat. anneles, 1865, 2, p. 191; Arwidsson, Bergens mus. aarbog, 1908, no. 11, p. 34; McIntosh, British annelids, 1910, 2, pt. 2, p. 462. Ophioglycera Verrill, Proc. U. S. N. M., 1885, 8, p. 436. GoNiADA EREMiTA Audouiii and iVIilne Edwards. Hist. nat. litt. France. Annehdes, 1834, 2, p. 247, pi. 6A, fig. 1-4; Qdatrefages, Hist. nat. anneles, 1865, 2, p. 191; Ehlers, Borstenwurmer, 1868, p. 704, pi. 24, fig. 49-51; McIntosh, British annelids, 1910, 2, pt. 2, p. 466. Locality. Georgia: off Savannah. Sta. 2419 (lat. 33° 34' N., long. 76° 40' 30" W.). Depth 107 fms. Bottom of fine grey sand with black specks. Bottom temp. 60.3° F. 2 April, 1885. One incomplete specimen. A species widespread, occurring on both sides of the Atlantic. On the American side it seems to be common in the more southern latitudes, but off the New England Coast it is rare as compared mth the well-known G. maculata Oersted. Chaetopteridae. In this highly specialized family the body is divided into either two or three distinct regions, of which the sharply defined anterior one is composed usually of from nine to fourteen somites. All hve in tubes of parchment-like texture, to which they are rather strictly confined and adapted. The prostomium is small and often mconspicuous. It is without append- ages, but usually bears a pair of eyes. The peristomium forms a collar which often almost completely encloses 364 THE ANNELIDA POLYCHAETA. the prostomium, though sometimes incomplete above, so as to leave the prostom- ium clearly visible. It bears a pair of often long and conspicuous grooved ten- tacles. It may or may not bear a second pair of shorter processes, often also spoken of as tentacles, but really representing modified parapodia in which traces of setae may sometimes be detected. The somites of the anterior division of the body are uniform. They are characterized by having their parapodia all strictly imiramous, the neuropodia not being developed. In the remaining part of the body the parapodia are bira- mous. Each neuropodium forms a bifid, or double, ridge, or torus, on which the uncini are arranged in several series. From differences in the character of the notopodia a median region in most forms is clearly distinguishable from a longer posterior one, the notopodia of the median region often being enlarged and highly modified into fin-like structures. The dorsal surface of the anterior region conspicuously flattened. Dorsally there is a markedly characteristic longitudi- nal median groove, which is cihated and which may extend over the entue length of the body, or may be interrupted. The thoracic setae in general are simple lanceolate or hastate forms. The fourth somite always bears one or more stouter setae of a special type. The neuropodia bear numerous seriate uncini which are serrate along their free, or distal, edges. Autotomy and regeneration are frequent in the family. Thus, in Chaetop- terus pergamentaceus Cuvier, as a result of unusual stimulus, autotomy takes place between the first and second somites of the median region, and may be followed by regeneration of a complete individual not only from the anterior fragment but also from the posterior one (See Gravier, Ann. sci. nat. Zool., 1899, ser. 9, 9, p. 129, 155). Potts, according to a recent paper (Proc. Zool. soc. London, 1914, p. 955), has found autotomy to be a very frequent and apparently normal method of reproduction in Phyllochaetopterus prolifica Potts. This accounts for the occurrence in the same tube of a number of individuals, a phe- nomenon that had been previously noted by Claparede (Annelides Chetop. Golfe Naples, 1868) for the allied Mediterranean species, P. socialis Claparede. The chaetopterids seem never to leave their parchment-like tubes, being among the most sedentary of the polychaetes. The tubes may be straight but connnonly are more or less strongly bent into a V- or U -shape, or sometimes nearly into that of a figure 8. In some, if not all, species of Phyllochaetopterus, the tubes are branched, and may be interconnected in such a way as to form extensive creeping systems, the tubes in, e.g., P. socialis forming dense masses, CHAETOPTERIDAE. 365 and in P. anglica Potts bundles of parallel di\dsions (Potts, Op. cit., p. 984). A current of water is kept constantly flo^\ang through the tube, primarily by means of the ciUa lining the dorsal groove. From this respiratory current food-materials are secured. The securing of food is aided by the usually long tentacles which ordinarily are protruded from the mouth of the tube and are moved over the surrounding surface, sweeping up diatoms and other small organisms which are carried by the current formed by their ciliated grooves to the mouth of the tube into which they are drawn.^ These annehds occm' between tide-marks and at moderate depths, though sometimes found in comparatively deep water. Other animals sometimes occur in the tubes of the chaetopterids as com- mensals. Thus in tubes of C. pergamentaceus {C. variopedatus) have been found Polynoe setossisima Savigny, Gattyana cirrhosa (Pallas), and the polyzoan Hypophorella chaetopteri (Joyeux-Laffuie) (C/. Archiv. zool., 1890, ser. 2, 8, p. 335). Key to Genera. a. Body divided into three regions. 6. Peristomiiim with a single pair of appendages (tentacles). c. Median region consisting of five somites of which the first bears separate fin-like notopodia and the others notopodia united across the dorsum to form conspicuous single fans or suckers. Chaclopteru^ Cuvier. cc. Median region consisting of two or three somites in which all tlie notopodia remain separate. d. Notopodia of median region bilobed and foliaceous Spiochaelopterus Sars. dd. Notopodia of median region unilobed and conical Mesochaetopterus Potts. bb. Peristomium with a second pair of smaller tentaculiform appendages in addition to the ordinary tentacles. (Notopodia of middle region foliaceous and bilobed or niultilobed). Phyllochaeloplerus Grube. aa. Bod}- divided into but two regions. 6. Not(i])odia of the posterior region all undivided Ranzanides, nom. nov.- bb. Notopodia of the posterior region all two-lobed Telepsavus Costa. Synonymy of Genera. The genus Tricoelia of Renier was established in 1848 with T. variopedatus as the type. But this species is identical with pergamentaceus, the type of Cuvier's Chaetopterus (1830) . Some authors, however, have given precedence to Renier's species, apparently under the assumption that Renier's Prospetto dei Vermi (1804) was pubhshed and distributed. If the species variopedatus is given precedence over pergamentaceus, then TricoeUa is valid and must be used instead ' For the more compUeated feeding methods see Enders, Life history and habits of Chaetopterus variopedatus, Journ. morph., 1909, 20, p. 479-431. -Pro Ranzania Claparede (1875), Tiec Bonaparte (1841), nee Bertoloni (1855). 366 THE ANNELIDA POLYCHAETA. of Chaetopterus and the name of the family must be Tricoeliidae. Mcintosh adopts variopedatus but recognizes 1848 as the date of publication, and in the synonymy Usts pergamentaceus with 1830 as the date, a procedure difficvdt to justify. While some pages of Renier's work were apparently printed, there is no evidence that his incomplete work was ever distributed , and in the Uterature no definite citations to it are to be found. The type of Grube's genus Phyllochaetopterus, gracilis, has not been iden- tified with certainty, I believe, since the time of its first description. Grube attributes but a single pah* of tentacular appendages to his form and describes these as short. It is generally assumed that Grube's specimens had lost the true tentacles. As the genus is now accepted, two pairs of appendages are present on the peristomium; but there must remain some doubt until gracilis has been reidentified and fully described, as to whether that species is really congeneric with the more recently described ones. Chaetopterus Cuvier. Regne anim., cd. 3, 1830, 3, p. 208. Tricoeiia Renier, Osserv. postume, 1848, p. 35. Chaetopterus pergamentaceus, Cuvier. Regne animal, ed. 3, 1830, 3, p. 208. Chaeloptents nnriegicus Sars, Beskr. og lagtt., 1835, p. 54, pi. 11, fig. 29a-29h. Tricoeiia varioyedata Renier, Osserv. postume, 1848, p. 35, pi. 8. Chaetopterus sarsii Sars, Nyt mag. naturv., 1863, p. 302. Chaetopterus insignis Baird, Trans. Linn. soc. London, 1864, 24, p. 477, pi. 49, fig. 1-S. Chaetopterus valencinii Quatrefages, Hist. nat. anneles, 1865, 2, p. 210, pi. 12, f. 1. Chaetopterus leuckartii Quatrefage.'^, Ihid., 18G5, 2, p. 216. Chaetopterus quatrefagesii Jodrdan, Not. zool. anat. Chaetop., 1809. Chaeliipltrui rarioj.edatus McIntosh, Brit, annelids, 1915, 3, pt. 1, p. 121. This interesting annelid appears to have a very wide distribution. De- scribed originally from the Caribbean Sea, it has since been recorded under vari- ous specific names from Norway and Sweden, the British Islands, and the coasts of France, Mediterranean Sea, Red Sea, coasts of New England and North Carolina, Strait of Magellan, and Chile. I am unable to find reliable differ- ences between specimens collected at Panama and those from the Atlantic side or between these and the European forms. C. pergamentaceus and norvegicus both have priority over variopedatus, the most commonly used name. Locality. Panama. March, 1891. Several specimens and a number of tubes. SPIONIDAE. 367 The membranous tubes are of the usual form and proportions. They were evidently found buried in shell-beds, as numerous fragments of shells closely cover the walls of the tubes, from which they stand out horizontally. Spionidae. In the members of this family the body, as a rule, is small, cyhndrical, and translucent, of varied and often bright colors, with the somites numerous. The prostomium is small, reduced to a narrow dorsal band, which may extend as far caudad as the fourth somite, though in some cases reaching only the second. Anteriorly it may be entire, or it may be somewhat incised, and thus with two short processes, but with no true tentacles. The eyes are most commonly four, sometimes more and at others wholly missing. Two elongate, tentaculiform, very contractile, and in most easily lost, palpi form a very charac- teristic feature of tliis family together with the Disomididae and Apistho- branchidae (Spionoidea). Peristomium without processes or setae. Proboscis short and simple, scarcely truly differentiated, but in some, at least, protrusible. Parapodia mostly biramous, both notopodium and neuropodium with a distinct lamella caudad of the setigerous branch, which bears two transverse series of setae. Setae all simple, of two principal kinds: — finer, limbate, capillary, setae and stout, hooded crochets of a type similar to those occurring in the Capitellidae and some Leodicidae. In addition, special, pale-like spines may occur on the fifth setigerous somite. Branchiae sunple, ligulate or cirrifonn, of variable number and position or in some wholly absent, often completely fused with the dorsal lamella. Anus more or less clearly dorsal in position, surrounded with cirri, papillae, or a cup-hke rim. These forms are ahnost strictly confined to the littoral region, one species, Nerine foliosa Sars, however, having been dredged from a depth of 725 fathoms. The larvae are widely distributed as pelagic forms, a considerable number of which have been described, though in most cases without definite reference to the corresponding adults. The period of pelagic life seems to be long. Some species Uve on sandy bottoms of varied character, in beds of mollusc shells, among rocks, and among Algae; others make tubes of sand or calcareous parti- cles. They feed upon diatoms, various other Algae, and such animal forms as 368 THE ANNELIDA POLYCHAETA. small Mollusca. They have marked powers of regeneration, renewing readily the anterior as well as the posterior region of the body.' The littoral habits of these annelids accounts for the fact that but a single species is represented in the collections of the Albatross, this being the widely distributed Boccardia polyhranchia (Haswell). Key to Genera. a. Fifth (or fourth) sctigerous somite not specially modified. h. With no branchiae. c. Body separated into two sharply distinct regions by difference in setae, the first nine somites bearing simple setae only, the others exclusively hooded crochets; ventral lamellae of more or less constant form, or changing but gradually Magelona F. Muller. cc. Body not thus divided into two sharply limited regions; ventral lamellae prominent only on the first four jiairs of parapodia Spiuphiincs Grube. 66. Branchiae present. c. Prostomium without frontal processes or cornua. d. Branchiae present on the first setigerous somite. e. Branchiae on the first somite only Streblospio Webster. ee. Branchiae present also on some succeeding somites. /. Only four or five pairs of branchiae Prionospio Malmgren. //. Numerous branchiae present. (J. These present only on the anterior region of the body. Laonice Webster and Benedict. (jg. Branchiae continuing to caudal end of body Spio Fabrioius. (Id. No branchiae on first setigerous somite, e. Branchiae beginning on the second somite. /. No crochets in notopodia. q. With anal cirri. h Hooded crochets beginning on the eighth or ninth somite Microspio Mesnil. hit. Hooded crochets beginning on fifteenth somite Mesospio Gravier. gg. Anal region cup-shaped, with no cirri Nerinides Mesnil. //. Crochets present also in notopodia. g. With anal cirri Aonides ClaparMe. gg. Anal region cup-shaped, no cirri Nerine Johnston. ee. Branchiae beginning caudad of the second somite. /. Dorsal lamella free from the branchia Spionides Webster and Benedict. //. Dorsal lamella fused with the branchia Pygospio Claparede. cc. Prostomium with frontal processes. d. Branchiae on first setigerous somite. c. Branchiae throughout length of body; no hooded crochets in notopodia. /. Body divided into two regions by a specialized somite, the sixteenth; dorsal cirri present on first four somites in addition to branchiae; a stout hooked seta on jiara- jiodia of first pair Morants Chamberlin. ff. Not so Scolelepis Blainville. ee. Branchiae absent from posterior region of body; hooded crochets also in notopodia. Scolecnlepides Ehlers. dd. Branchiae beginning on second setigerous somite (hooded crochets in notopodia). MarcuzcUcria Mesnil. (/((. I'jithcr the fifth or the fourth setigerous somite specially modified. 6. The fifth somite specially modified, bearing stout paleae. c. Branchiae beginning on the second setigerous somite Boccardia Carazzi. ' CJ. Mesnil Bull, scient., 1897, 29, p. 201, 209. Also Nussbaum, Zeitschr. wiss. zool., 190.5, 79, pi. 13-10; Giard, Compt. rend Assoc. Frangai.se, 1901, p. 153. DISOMIDIDAE. 369 cc. Branchiae beginning caudad of the fifth setigerous somite. d. Hooded crochets beginning on the seventh setigerous somite Polydora Bosc. dd. Hooded crochets first appearing on the eighth setigerous somite Carrazki Mesnil. hh. The fourth setigerous somite specially modified. Reproducing by terminal buds as in many .syllids Polydorella Augener. Synonymy of Genera. Nerinopsis Ehlers (1912), based upon certain pelagic and larval specimens (Chaetosphaera) secured by the Gauss as well as by the British National Antarctic Expedition, is of doubtful position. Even the largest specimens wholly lacked the hooded crochets characteristic of the other spionids, and the form is placed by Ehlers in the Spionidae with some doubt. Hekaterobranchus Buchanan (1890) seems to be the same as Streblospio Webster (1879) as at present defined. Leucodore Johnston is synonymous with Polydora Bosc. Malacoceros and Uncinia Quatrefages and Colobranchus Schmarda are synonyms of Scolelepis Blainville. Scolclepis Blainville has been subsequently wTitten in the modified form Scolecolipis by Malmgren and others. Chaetosphaera Hacker was proposed for certain widespread spionid larvae, the affinities of which are not yet known. BOCCARDIA. Carrazzi, Mitth. Zool. stat. Neapcl, 1893, 11, p. 15. BoCCARDIA POLYBRANCHIA (HaSWell). Puhjdora polijbmudUa Harwell, Proc. Linn.. sec. N. S. W., 188.5, 10, p. 273; Lo Bianco, Atti H. acad. sci. fis. nat. Napoli, 1893, 5, no. 11; Ehlers, Fostsch. K. gesellsch. Gottingen, 1901, p. 164. Boccardia polybranchia Carazzi, Mitth. Zool. stat. Neapel, 1891, 11, p. 1.5, pi. 2, fig. 1-3; Mesnil Compt. rendus Acad, sci., 1893, 117, p. 643. > Polydora (Bocciirdia) polybrii.ii.chia Mesnil, Bull. sci. France Belgiquo, 1896, 29, p. 221; Ehlers, Polych. Magahl. sammel., 1897, p. 87; Nach. Geselsch. wiss. Gcittingcn, 1900, p. 217. A single specimen of this species is in the collection, Ijut labeled simply Albatross. The species occurs commonly on the South American coast as well as in the Australian region. DiSOMIDlDAE. Key to Genera. a. Prostomium without tentacular processes; both neuropodial and notopodial cirri well developed on the first parapodia; notopodial setae of the most posterior somites stout spines forming star- shaped dorsal clusters Disomides, nom. nov. 370 THE ANNELIDA POLYCHAETA. aa. Prostoniium with a small anterior median process; notocirrus of first parapodia rudimentary; notopodial setae of the most posterior somites stout crochets arranged in transverse rows. Paecilochaetits Claparede. Synonymy of Genera. Disoma Oersted and Poecilochaetus Claparede, formerly included in the Spionidae, were removed as a distinct family by Mesnil (Bull. sci. France Belgique, 1897, 30, p. 97), a procedure that seems amply justified. The two genera are clearly distinct and may be separated as indicated above. Since Disoma Oersted is preoccupied by Disoma Ehrenberg (Polyg., 1844), it is here replaced by Disomides and the family name is altered accordingly to Disomididae. Other spionid genera, Magelona, Polydora, and Nerine of the Magelonidae, Polydoridae or Leucodoridae, and Nerinidae respectively have also been re- garded as types of distinct families; but at present there seems no clear justifica- tion for these families. ClHRATULIDAE. The body of these annehds is elongated and linear, consisting of short somites which are numerous, sometimes exceeding three hundred and fifty. They are generally small or moderate in size, but may be as much as 300 milli- meters long. They undergo strong retraction in preservation, often contracting to half their length. The color is nearly always uniform and some shade of brown or green, but may be a brighter shade of red ; and occasionally the body is colored in spots over a paler background, as in Cirratulus punctatus Grube. The Uquid or plasma of the blood is red, containing haemoglobin, tliis giving to the lateral brancliiae a similar tinge and resulting in a characteristic appearance in these forms. The prostomium is distinct, but much reduced in size, and is always devoid of appendages. Eyes present or absent; often present in young stages and absent in adults. The mouth is ventral in position. The peristomium and two somites succeeding it are achaetous. On one or more of the anterior somites there may or may not be present dorsal tentacular cirri or large tentacuUform organs, recalling those of Spionidae, either dorsal or ventral in position. Notopodial and neuropodial fascicles of setae are present, making the para- podia technically biramous; but there are no traces whatsoever of setigerous protuberances or of either dorsal or ventral cirri, the body in consequence resembling that of lumbrmereids or of some oUgochaetes. CIRRATULIDAE. 371 The setae are mostly simple, capillary, or aciculiform, rarely composite (Acrocirrus). Commonly capillary setae and crochets occur in the notopodia, while usually shorter capillary setae and crochets, or crochets alone, may occur in the neuropodia. Mostly long and fihform branchiae, which are contractile, occur in a dorso- lateral position on a variable number of somites. The proboscis is always unarmed. Epitokous forms are frequent in the genera of the subfamily Dodecaceriinae, established below, but are not known in those of the Cirratulinae proper. Some species develop both smaller, pelagic, epitokous forms and larger, sedentary, epi- tokous forms, as Caullery and Mesnil in their brilliant work on epitoky in this family have so thoroughly demonstrated for Dodecaceria coricharum Oersted.^ In the epitokous stage, as also observed so frequently in other families having similiar pelagic forms, the notopodia tend to develop very long and fine nata- tory setae. Modifications in the eyes and in the musculatm'e have also been observed, e.g., in D. concharum. In the epitokous stage in Dodecaceria the palpi tend to atrophy and the forms then may for the time conform nearly to the definition of Cirrineris Blainville. Mesnil and Caullery find D. concharum in its first or ordinary form to be parthenogenetic. It is in this stage also vivipa- rous. Viviparity has also been detected in Cirratulus chrysoderma Claparede. Some species formerly described as belonging to Grube's genus Heterocirrus are sho\vn to have been based on stages of Dodecaceria {e.g., Heterocirrus saxicola Grube and H. fimbriatus Verrill, being epitokous phases of Dodecaceria con- charum Oersted). The cirratuUds live mostly in or near the littoral region though occasion- ally descending to as much as 1,250 fathoms, as in the case of Chaetozone bentha- liana Mcintosh of the Challenger expedition. They hve by preference in muddy sand and are frequently found in slime of a putrid odor. Dodecaceria concharum takes its specific name from the fact that it frequents burrows in calcareous rocks and particularly old and broken shells; it also occurs in the calcareous Algae, such as Melobesia and Lithothamnion," and bores even in sand- stone. This species is frequent in oyster shells. The alimentary tract of ckrat- uhds has been found to contain mud in which are noted fragments of such ' See Mesnil and Caullery, Sur I'existence des formes epitoqiies chez les annolidcs de la famille dos Cirratuliens, Corapt. rendus Acad, sci., 1896, and, more particularly, Les formes epitoqucs et revolution des cirratuliens, Ann. Univ. Lyon, 1898, p. 189. 'Cf. Gravicr, Nouv. .arch. Mus. hist, nat., 1908, 10, p. 1.51, and Mcintosh, British annelids, 191.5, 3, pt. 1, p. 256, 257. 372 THE ANNELIDA POLYCHAETA. forms as small Crustacea, spicules of sponges, foraminifers, radiolarians, and diatoms (Mcintosh, Challenger Annehda, 1885, p. 383-385). The classification of the cirratulids is not in a wholly satisfactory condition either as to genera or as to species. A revision is much needed that shall be based upon a thorough study of type-species and their development along the lines so well initiated by CauUery and Mesnil. Until this is done the significance or reaUty of certain genera must remain problematical. In the following key the genera are taken up as more commonly conceived. Key to Genera. a. Without large prehensile tentacles CirratuHnae, subfam. nov. b. Only lateral branchial filaments present, these occurring usually on nearly all somites. Cirrineris Blainville. bb. Some dorsal filaments or cirri present in addition to the lateral ones. c. The dorsal cirri occurring on the first setigerous somite and often on one or more of the follow- ing ones as well Cirratulus Lamarck. cc. No dorsal cirri on the first one or more somites, but these present on one to several of the fol- lowing ones Audouinia Quatrefages. aa. With large prehensile tentacles (recalling those of the Spionidea). . . . Dodecaceriinae, subfam. nov. b. Body with two divisions, an anterior of nine somites and a posterior, of which the first somite is twice as long as those of the anterior region and bears different and shorter setae and crochets. Cirratulispio Mcintosh. 6b. Not so. c. Branchiae few in number (one to eight pairs). d. Palpi borne on the prostomium; composite setae present. e. Branchiae present on the first metastomial somite. /. First metastomial somite bearing two pairs of branchial filaments. . . .Aarocirrus Grube. ff. First metastomial somite bearing only a single pair of branchiae. Ledon Webster and Benedict. ee. No branchiae present on the first metastomial somite Macrochaela Grube. dd. Palpi borne on the first metastomial somite; setae all simple. Branchiae from four to eight pairs Dodecaceria Oersted. cc. Branchiae rather numerous. d. Acicular setae adorning nearly the entire circumference of the posterior somites. Chaelozone Malnigren. dd. Acicular setae not thus encircling the posterior somites. e. Acicular setae, either entire or bidcnf ate, occurring in both notopodia and neuropodia. CauUerieUa, gen. nov.' ee. Setae all fine, capillary Tharyx Webster and Benedict. CiEEiNEEis Blainville. Diet. sci. nat., 1828, 57, p. 488; St. Joseph, Ann. .sci. nat., 1894, ser. 5, 17, p. 42; Mesnil and Caullerv, Ann. Univ. Lyon, 1898, p. 110. Cirrhineris Quatrefages, Hist. nat. anneles, 1865, 1, p. 462. Labranda Kinberg, Ofvers. K. vet. akad. Forh., 1865, no. 4, p. 255. 1 Genotyjae, C. I'iridis (Langerhans) (Cirratulus viridis Langerhans). Including also Helerocirrus ccj.ut-csncis St. Joseph, Cirrahdus jragilis Leidy, and perhaps Cirratulus bioculatus Keferstein. CIRRINERIS NESIOTES. 373 CiRRINERIS NESIOTES, Sp. UOV. Plate 70, fig. 5, 6. The general color of the body in the type is at present dark grey, of a some- what greenish or brownish green cast. The branchiae are yellow. The body is relatively stout. It is widest at the anterior third or fourth, from where the body narrows continuously caudad, the caudal region being slender and subconically pointed. From the widest region the body narrows conically cephalad. The number of setigerous somites is nearly 190. The total length is near 55 mm. ; the greatest width, 6.25 mm. The prostomium is somewhat flattened, subtriangidar in outhne, but with the anterior end well rounded. Its surface is irregularly roughened with nodu- lar elevations and depressions. There are some vaguely darkened areas and many very fine dark specks, but whether these represent eyes or not cannot be decided in the specmien as it is at present. The peristomium widens continuously caudad from the prostomium, with which it forms a rather narrow cone. In length it is 2.2 mm., its width at base being a Uttle greater, about 2.5 nmi. Dorsally it is divided by transverse sulci into seven or eight short, in part incomplete, bands or partial annuU, the surface of which is broken up into mmierous small areas by a reticulation of finer sulci. The ventral surface is smoother than the dorsal. It shows three principal but not clearly separated divisions. The border of the mouth is crossed by num- erous, fine, radiating sulci, as usual. The first setigerous somite is longer than the succeeding, the second a little shorter, the third and fourth further decreasing, while a considerable number of those inunediately following are extremely short. Toward the widest part of the body the segments increase very materially in length but are always propor- tionately very short and closely crowded. In the widest part of the body the width of a somite is eighteen or more times the length. Dorsally the fu-st and second somites are roughened by reticulating sulci like the dorsum of the peristomium, the succeedmg segments quickly assuming a smooth condition. The setigerous segments are all distinctly separated from each other and are undivided. The brancliiae when fully extended have a maxunum length of about 10 mm. In the preserved specimens they do not curl spirally, but remain extended or irregularly bent. They occur on all segments nearly to the caudal end, or excepting on the last seven to ten. They are of the same stoutness posteriorly as anteriorly, or nearly so. The ordinary branchiae are inserted a Uttle above 374 THE ANNELIDA POLYCHAETA. the notopodial tubercle on the anterior segment; the distance of the point of insertion increases caudad, and in the middle and caudal regions approaches, but does not fully equal, the distance between the neuropodial and notopodial tubercles. No special branchiae can be detected in the type. Neither tentacles nor scars of any can be found. The setigerous tubercles on each somite are widely separated, the distance between them in all parts exceeding that between notopodium and point of insertion of branchia (in the middle region, about 1.8 mm. instead of 1.2 mm., and near the beginning of posterior third, 1.6 nmi. instead of 1 mm.). Neither the setigerous tubercles nor the branchiae arise from any ridge. Where the branchiae have fallen off a longitudinal furrow is seen along the line of their insertions. The ventral spines are detected first on from the thirty seventh to the thirty ninth setigerous somite, or near that region. On the more anterior somite they are three in number but quickly rise in the widest part of the body to four or rarely five, though somites with but three may occur between those having the larger number. Caudad the number again falls to three, and this is the number occurring throughout most of the body length. The most anterior ventral spines are shorter and straight, or nearly so, the size increasing caudad and the exposed region becoming conspicuously curved, with the concavity cephalad. They are dark colored and strongly cross-striate. (Plate 70, fig. 5). The notopodial spines seem to occur first about twenty somites farther caudad than the first of the ventral ones. They are paler and more slender than the ventral ones, and in each notopodium there are five or four, or the number rises to six farther caudad on the somites that bear but three, much stouter, neuro- podial spines. Locality. Galapagos Archipelago: Chatham Island. Shore. 18 January, 1904. One specimen. This species is distinguished from others of the group primarily by the arrangement of the setae and spines, namely, in having in both series only capillary setae on the most anterior, and in the others both capillary setae and spines. C crassicolis (Kinberg) from near Honolulu differs, e.g., in the arrange- ment of spines, in the gi-eater relative stoutness of the anterior branchiae, and the fewer segments. CiRRATULUS Lamarck. Anim. s. verteb., 1801, 5, p. 300; Johnston, Cat. annelids Brit, mus., 1865, p. 209. Cirrhatulus AuDouiNand Milne Edwahds, Hist. nat. litt. France. Annelidcs, 1834, 2, p. 2G8; Qu.\tre- FAGES, Hist. nat. annelos, 186.5, 1, p. 454. CIRRATILUS MEGALUS. 375 Cirrhatvla Templeton, Mag. nat. hist., 1836, 9, p. 234. Timarale Kinberg, Ofvcrs. K. vet. akad. Forh., 1865, no. 4, p. 254. Promenia Kinberg, Op. cit., 1865, no. 4, p. 254. Archidice Kinberg, Op. cit., 1865, no. 4, p. 255. CiRRATULTJS MEGALTJS, Sp. nOV. Plate 70, fig. 1^. Special branchiae on first setigerous segment in a group of at least eight on each side, the two groups widely separated by a naked dorsal area. A single branchia on the second somite on each side. The number of setigerous segments in the two specimens is nearly 186 and 205 respectively. Total length 260 mm.; greatest width about 13 mm. The color of the preserved specimens is a somewhat brownish grey, of a greenish cast. A pale median longitudinal ventral line. Branchiae yello^^dsh. The body is stout, widest near the middle and strongly tapering towards both ends, with the caudal end somewhat the more pointed. The dorsal sur- face is strongly convex, hemicyUndrical, while the ventral surface is fiat. There is a conspicuous, fine, median longitudinal sulcus along the dorsum, the sulcus deepest on the Une separating the somites. The prostomium is short and wide. Anteriorly convex, semicircular; depressed a little above the anterior margin, with a weak median longitudinal sulcus. No eyes evident. (Plate 78, fig. 1). Peristomium long, equalMng the succeeding seven somites. Partially and irregularly di\'ided into three rings above and laterally. Of these rings the last two are divided by a transverse sulcus above, and the second has a median dorsal triangular impression at its caudal border. The anterior ring is crossed above and in front by a deep sulcus which at the middle is semicircularly curved for- wards. Beginning near each side of the mouth is a weak furrow which runs caudad and mesad to meet the one from the opposite side at the midventral Une on the caudal edge of the peristomium. The ventral area enclosed by these furrows is divided by a transverse sulcus into a nearly smooth triangular area and an anterior area between this and the mouth which is di\'ided by transverse sulci into four narrow transverse bands. Along the dorsolateral surface, espe- cially of the caudal ring, are some short longitudinal sulci. The caudal border of the mouth is divided into radiating ridges by numerous fine sulci. (Plate 70, fig. 4). The first somite is longer than those succeeding ; above it is conspicuously. 376 THE ANNELIDA POLYCHAETA. sublongitudinally wrinkled. The succeeding segments are smooth; they are undivided above but show ventrally a vague transverse line marking off a shorter caudal from a longer anterior part. The anus is small, circular, and terminal, opening somewhat more dorsad than ventrad, the ventral border projecting somewhat caudad. The setigerous segments are all distinctly separated; in the type they are about one thu'teenth as long as wide and further caudad may be as much as one seventh. The branchiae are numerous, and their precise proportionate length cannot be determined because of their tangled and broken condition, but would seem at most not to exceed four times the diameter of the body. The branchiae occur in pairs on all the segments of the anterior region and caudad in the large speci- men, as judged by the scars, to about the seventeenth segment from the caudal end. In the anterior region each branchia is inserted at the edge of the dorsal continuation of the elevated ridge bearing the setae ; the distance of the branchiae above the notopodial tuft increases caudad to the middle region of body, over which the distance remains essentially constant, this being in the type about 3.2 nrni. The vertical ridges above the notopodia become less distinct and finally obliterated caudad. The special branchiae occm- in a tuft on each side of the first setigerous somite. The exact number in each tuft could not be determined, but in the paratype it seems to be between twelve and eighteen. They do not extend far up the side, there being a wide naked region on the dorsum. The setigerous tubercles are, as usual, well separated, though in the middle region the distance between them is much less than that between notopodium and the branchia (1.8 mm. as against 3.2 mm.). They are borne upon a ridge, the upper end of which is extended beyond and bears at its edge the branchia. The ventral spines, as nearly as could be determined, appear first on the fifty fifth somite in one specimen and the sixty fifth in the other. The dorsal spines could be found first on about the one hundred and twentieth somite in one, and the hundred and sixty fifth in the other, but the bad condition of the specimens renders some error likely. The most anterior ventral spines are pale, these caudad soon becoming darker and stouter. The number of ventral spines is two or three, three being the maximum. These spines in the posterior region are dark, stout, and straight, and show both cross and longitudinal striations. (Plate 70, fig. 3). The anterior spines are paler and rather less stout. The dorsal spines are paler and more slender. The capillary setae are long, those of the notopodia being longer than the neuropodials. They are finely closely serrate on one side throughout their length. (Plate 70, fig. 3, 4). CIRRATULUS SININCOLENS. 377 Locality. Off Peru: Sta. 4653 (lat. 5° 47' S., long. 81° 24' W.). Depth 536 fms. Bottom of dark brown volcanic mud. Bottom temp. 41.3° F. 12 November, 1904. Two specimens. This species is exceptional in its large size and in the considerable depth at which it lives, the members of the genus being almost exclusively littoral. It has resemblances to C. capensis Schmarda, but has the special branchiae on the first instead of on the second somite, has the somites of a different proportion, the ventral spines without the curvature characterizing those of that species, etc. Cirratulus capensis is also a large species, the maximum length recorded being 200 mm., with a maximum width of 9 nun., which is considerably smaller than the type of the present species. Cirratulus sinincolens, sp. nov.^ Plate 70, fig. 7-10. The general color of the types at present is grey, in parts of veiy slight brownish tinge. The larger of the two type-specimens is incomplete caudally, sixty five somites being present. Its total length is about 60 mm. and the maximum width 11.5 nun. The smaller specimen is complete. It has a total length of about 95 mm., a maximum width of 7.5 nun., and consists of 107 or 108 somites. The general form of the body is essentially as usual in the genus, broadest and highest in front of the middle, and tapering at both ends. The dorsal surface strongly convex, the ventral flat. The prostomium is short and broad. In outline as seen from above with the anterior margin semicircularly rounded, on the lateral portions more flat- tened, and giving the appearance, roughly, of a trapezium or truncate triangle with the sides toward the base flaring ectad. The prostomium is much highest across the caudal end, being strongly transversely depressed in front and the slope of the caudal portion very steep, not marked with any distinct longitudinal furrow. On each side separated from proboscis by a deep, vertical sulcus which extends from the border of the mouth toward the dorsum, upon which it does not extend, setting off a caudal band. This band is essentially fused with the peristomium above. The sulcus is weak in the smaller specimen. The peristomium is abruptly more slender than the succeeding portion of ' sinus, gulf, incolere, to inhabit. 378 THE ANNELIDA POLYCHAETA. the body, cylindi-ical in form, and long, its length equalling that of the suc- ceeding seven somites taken together. On each side deep sulci separate off six (or five in the smaller specimen) vertical bands, but the sulci are not continuous with other, finer, sulci across the dorsum or with others across ventral surface, which are scarcely evident in the smaller specimen, a division into rings being thus incomplete and irregular. There is a longitudinal depression along the lower portions of each side. In the larger specimen, a longer, broad, trapeziform band in place of the triangular area in megalus is set ofT by a deeper furrow, the oblique lateral furrow extending up on the side. In front of these are four narrower transverse bands, the dividing sulci between which become vaguer cephalad. The anterior ventral margin is widely concave. The first metastomial somite is larger than the succeeding ones, though not fully as long as the next two taken together. Dorsally it is marked with irregu- lar sulci or wrinkles, giving a coriarious appearance. The succeeding somites increase gradually in width and height to the wide region of the body, but increase only slightly in length. They are all wholly simple, transverse sulci occurring neither above nor below. The surface of all, as preserved, is coriarious. The anus is terininal and transverse, somewhat crescentic, the ventral border projecting convexly dorsad. The border is divided into six lobes, a large median ventral one, one at each end, and three in the arch above. The setigerous tubercles are widely separated, in all cases clearly exceed- ing the distance between notopodium and branchia. They are distinct and conical. In the broad region in front of the middle in the larger specimen the tubercles are about 1.5 nam. long. They are at the opposite ends of distinct vertical ridges, which are not extended dorsad bevond the notopodium to the branchia as they are in the case of megalus. The poorly preserved and much rubbed condition of the types does not per- mit a whoUy satisfactory study of the setae. Mounted parapodia from sev- eral regions of the body show in all cases two types of capillary setae. In each notopodium on the ventral side, and in each neuropodium on the dorsal side of the fascia, a number of exceedingly fine capillary setae which run out into very fine tips (Plate 70, fig. 10), and, below these, more numerous, much coarser and longer setae, wliich are also attenuated distad into very fine, smooth, and com- monly curved tips. Below the tips along one side these setae have a close series of scales or fine serrations. These setae are finely longitudinally fibrillated. (Plate 70, fig. 9). In the neuropodia of the posterior region, at least, there is, ventrad, of the principal setae and standing somewhat apart from them, an CIRRATULUS DANIELSENI. 379 obviously stouter single seta or spine which probably represents a crochet. It is strongly longitudinally fibrillated, acutely pointed distad and, so far as made out, whoUy lacked any marginal serration. (Plate 70, fig. 8). The distribution forward of this spine could not be followed with certainty. Branchiae in general occur, a pair on each somite, back at least as far as the eightieth somite. Each of the paired branchiae is inserted above the notopodium toward the caudal border of the somite, the distance above the notopodimn not being large. The branchiae are fihform, distally pointed, and long, though most are broken off and could not be measured. In the smaller specimen, a possibly complete branchia on about the twentieth somite is but 6 mm. long, while one near the eightieth somite measured 20 mm. The spe- cial branchiae are on the first somite. On the left side in both specimens there is a single branchia just above the notopodium; above this is a shghtly raised mound from which one long and one short branchia arise, in the smaller specimen the one appearing as a branch from the base of the other. In this specimen, too, the single, or ventral, branchia is very small, probably in process of regeneration. On the right side in both specimens are thi'ee branchiae aris- ing close together in a single group from a common elevation, of which one ^s long and two short. There is a very wide, naked, dorsal area between the two groups of branchiae. Locality. Gulf of CaUfornia: Sta. 3435 (lat. 26° 48' N., long. 110° 45' 20" W.). Depth 859 fms. Bottom of brown mud with black specks. Bottom temp. 37.3° F. 22 April, 1891. Two specimens. This species would seem to be well characterized tlu'ough the almost com- plete obliteration of crochets as such, the high number of partial divisions in the peristomium, and the fewness of the special branchiae, with theu- situation on the first setigerous somite. It is much smaller than the preceding species and larger than C. robustus Johnson occurring farther north in the littoral region. CiRRATULUS DANIELSENI Hansen. Mem. cour. savants c'trang., 1881, 44, p. 17, pi. 5, fig. ll-l."]. This species, described originally from the Bay of Rio de Janeiro, conforms to Timarete as defined by Kinberg. Locality. — Brazil: Abrolhos, off the Coast. 28 December, 1887. One well-preserved specimen. 380 THE ANNELIDA POLYCHAETA. AuDouiNiA Quatrefages. Hist. nat. annelcs, 1865, 1, p. 459. AUDOUINIA FILIGERA NESOPHILA, SUbsp. nOV.^ Plate 70, fig. 5, 6. The general color of the body is a somewhat slaty black. The branchiae are bright yellow. The body is moderately slender. It is conically pointed at both ends, but the caudal end is somewhat more slenderly so. The middle two thirds or three fourths of the length is nearly uniform in thickness. The total number of seti- gerous somites is in the neighborhood of 390. The total length is 75 mm.; the greatest width about 3.5 mm. The prostomium is subcorneal, flattened, with the anterior end bluntly rounded. It is abruptly narrower than the peristomium. No eyes detected. The peristomium is longer than the prostomium in about ratio of three to two. It is in outhne roughly trapeziform, with the lateral borders convex. The dorsal surface is divided by transverse and cross sulci into a number of irregular rounded tubercles or areas. It appears as usual to be formed by the fusion of three primary somites. The length of prostomium and peristomium together is dr. 1.1 mm.; the width at base dr. 1.8 mm. The border of the mouth is radially wrinkled, as usual. The first setigerous somite, as usual, is longer than the second, those fol- lowing reducing gradually and being very short. From the end of the anterior fourth or fifth the segments increase somewhat in length, but remain of nearly uniform length over the middle and posterior regions. At the middle of the body the somites are sixteen or seventeen times wider than long. The somites in general are thus very short and closely crowded. All are distinctly separated from each other. Ventrally they show an indistinct division by transverse suture into two very unequal parts, the caudal of these being the shorter. The branchiae in general are fine and cirriform, those of the anterior region being but httle coarser than those of the posterior. The longest noted had a length of 15 min., being thus four or five times the width of the body in the middle region. The branchiae in the anterior region arise in contact with the dorsal setigerous tubercle and farther back the point of insertion is but little removed from it. The paired branchiae occur anteriorly on all setigerous somites except apparently the first. The special branchiae occur on the seventh setigerous 'j^ffos, island, and^c^iXos, loving. DODECACERIA CONCHARUM. 381 segment ; they form a band across the dorsum, with the filaments more closely crowded laterally. The upper and lower fasciae of setae are separated by a moderate space, the distance between them in the type being only .6 or .7 mm. The tubercles are weak and do not arise from any distinct ridge such as occurs in many species {e.g., C. megalus). Spines occur in most of the ventral fasciae. They are proportionately stout and their apices project freely but a short distance. In each fascicle there are three, or less conmaonly, four spines. They occur well forward, but the seg- ment on which they first appear could not be determined with certainty. (Plate 70, fig. 5) . The spines of the notopodia are paler and more slender, and are more numerous in each fascia. The capillarj^ setae relatively long. (Plate 70, fig. 6). Locality. Easter Island: 20 December, 1904. Shore. One specimen. Audouinia filigera Delle Chiaji is used here as by Ehlers (Abh. K. gesellsch. wiss. Gottingen. Math. phys. klasse, 1901, p. 183), to include also A. lamarckii Audouin and Milne Edwards (1840). Other sjmonymous names are auslralia Gay (1859) and cMajei Marenzeller (1888). The unsatisfactory condition of the classification of this and related genera makes it difficult to determine species, in the absence of extensive material, from the hterature. The large number of somites proportionately to length in the present form is noteworthy. It seems to differ from the species also in coloration and in proportions. A. filigera is conmion along the Chilean and Patagonian Coasts, as well as in the Atlantic. Ehlers did not find any Chilean or Patagonian specimen having the dorsal branchiae inserted on the seventh somite as in the present form, though such occur in the Atlantic {lamarckii). St. Joseph (Ann. sci. nat., 1894, ser. 5, 17, p. 51) notes variations in this respect. Marenzeller (Zool. jahrb. Syst., 1888, 3, pt. 1, p. 16) records a form of this species, variety vieridionalis, from Angra Pequena Bay. DoDECACERiA Oersted. Annulatorum Danicorum conspectus, 184.3, p. 44; Mesnil and Caullery, Ann. Univ. Lyon, 1898, p. 116; McIntosh, British annelids, 1915, 3, pt. 1, p. 254. Heterocirrus Grctbe, Archiv. naturg., 1855, 21, p. 108. Dodecaceria + Helerocimis Quatrefagew, Hist. nat. annelds, 1865, 1, p. 465 (in part). Naragansela Leidy, Journ. Acad. nat. sci. Pliilad., 1855, ser. 2, 3, p. 144. Dodecaceria concharxjm Oersted. Annulatorum Danicorum conspectus, 1843, p. 44, fig. 99; Mesnil and Caullery, Ann. Univ. Lyon, 1898, p. 5, pi. 1, 2; McIntosh, British annelids, 1915, 3, pt. 1, p. 255. INereis sextentacutata Delle Chiaji, Mem. anim. regn. Napoli, 1828, 3, p. 176, pi. 43, f. 16. Cirratulus concharum Grube, Fam. annel., 1851, p. 68. 382 THE ANNELIDA POLYCHAETA. Terebella astreae Dalyell, Pow. creat., 1853, 2, p. 209, pi. 26, fig. 10. Naraganseta corallii Leidy, Journ. Acad. nat. sci. Philatl., 1855, ser. 2, 3, p. 144, pi. 2, fig. 46-48. Heterocirrus saxicola Grube, Archiv. naturg., 1855, p. 109, pi. 4, t. 11. Helerocirrus saxicola Marion and Bobrbtzky, Ann. sci. nat., 1875, ser. 6, 2, p. 67. Heterocirrus fimbriatus Verrill, Check-list marine invert. Atlantic coast, 1879, p. 11. Locality. Off Newfoundland : Sta. 2446 (lat. 46° 20' N., long. 49° 52' W.) . Depth 40 fms. Bottom of broken shells. Bottom temp. 35.5° F. The anterior half of one specimen. Opheliidae. These are forms always of small or moderate size, the largest rarely exceed- ing six centimeters, with the number of somites mostly between twenty-five and forty. The color in life is most commonly a rose or pinkish red, due to great vascularity, to which is commonly added a purplish or other hue due to irides- cence at the surface of the cuticle, which is smooth and glistening. The prostomium not stronglj^ differentiated; either rounded in front or conically pointed, often with a median i:)rolongation or tentacle. Ciliated nuchal organs are exsertile from pits located posteriorly. Eyes may or may not be present. Peristomium without tentacular cirri, but normally setigerous and often with setigerous papillae. The somites in general are subdivided into a number of distinct annuli; rarely the somites are not superficially divided ofT from each other. In some genera eyes occur along the sides of the body, also peculiar segmental sensory pits. The parapodia are not conspicuously developed. They are structurally biramous, though the notopodial and neuropodial setae sometimes are merged into a fascia essentially single. Setigerous papUlae either present or absent. Notocirri sometimes absent, but more commonly present as branchial organs, and either occurring over essentially the entire length, or else restricted to one region, — anterior, posterior, or mecUan. Neurocirri may also be present, but are more frequently absent or aborted. The setae are all capillary and simple. They may be wholly smooth, limbate, or serrulate. Often they are rudimentary over part or all of the body, and rarely not superficially evident. The nephridia occur in a considerable number of somites of the posterior region as pau-ed tubules with open, ciliated, internal funnels and opening exter- nally by nepliridioiDores, as usual. OPHELIIDAE. 383 The blood is reddish from the presence of haemoglobin. It contains a number of rounded and in part, at least, amoeboid corpuscles, which are colored with haemoglobin from the surrounding medium. The fluid gives its color to the brancliiae and commonly to the body in general. There is a short, evaginable proboscis, often forming a simple button, with rosette-like folds. Intestine commonly filled with sand or other material from the medium in which they live. The opheliids live in large part in pure sand, but often occiu- in sand mixed with mud, or in mud or slime sometimes of a strongly odoriferous character. They burrow in the sand and mud like lancelets. WTiile they are essentially shallow water forms, some occasionally are found at considerable depths; and Kesun fusus, the interesting form described below (p. 38G) was secured at the great dei)th of 2,463 fathoms and Travisia 'profundi at 2,222 fathoms, depths much exceeding any other recoided for the family. The resemblance to Amphioxus in habits of many species is accompanied by a corresponding superficial resemblance in form, as well as in size, trans- lucency, consistency, movements, and distribution, as pointed out by Willey (Ceylon pearl oyster fisheries report, 1905, pt. 4, p. 288) in his note on Armandia lanceolata: "Although infinitely removed from each other in morphology, Armandia and Amphioxus ai'e closely approximated in bionomics. It is a case of true homoplasy; there is no question of affinity, nor of mimicry, nor of paral- lel evolution." These resemblances were previously pointed out by Lo Bianco (Atti R. acad. sci. fis. nat. Napoli, 1893, ser. 2, 5, no. 11) for another species of the same genus, Armandia polyopthalma. Some forms are very sluggish, such as Ophelia limacina and, in general, other species of this genus and also the species of Travisia. In captivity these forms exhibit merely slight elongations and contractions, or roll about rather inertly, sometimes thrusting the snout here and there. The strong muscular development, however, indicates considerable power in bm-rowing. On the other hand, as pointed out by PhiUippson (Zool. anz., 1899, 22, p. 417), Polyopthalmus is specialized for locomotion, and the contrast it affords with the preceding highly sedentary type, he thinks, clearly exhibits the artificiality of the much used division of the polychaetes into the Sedentaria and Errantia. Also very active is Ammotrypane, Mcintosh (British annelids, 1915, 3, pt. 1, p. 17, 21) remarking in regard to A. aulogaster: "The' extraordinary activity and vigor of the hving animals at once attract attention. They exceed most armelids in the display of violent muscular action, as they rush about in every direction through water or sand, mucus or mud, and then 384 THE ANNELIDA POLYCHAETA. generally plunge into sand." And of Armandiella roberiianae: "Like its congeners tliis species is an active inhabitant of muddy sand, and it swims through the sand swiftly, like an eel." They live upon organisms occurring in the medium they frequent. In the sand or mud in their intestines are found sponge-spicules, diatoms, radiolarians, Foraminifera, and the remains of various other organisms. Key to Genera. a. Lateral eyes present along the body and often on the prostomium ; branchiae none, or but rarely present (Armandiella) Polyopthalminae. b. No cirri or branchiae present; somites distinctly separated, c. Prostomium bearing a median process or tentacle in front; eyes with crystallines. Arrnandia FiUppi. cc. Prostomium without median process in front, rounded; eyes without crystallines. Polyopihalmus Quatrefages. 66. Lateral cirri or branchiae present; somites not distinctly separated Armandiella Mcintosh. aa. No eyes either on body or on prostomium, or rarely present, when present, branchiae also present; branchiae present, or rarely absent. 6. No branchiae (or cirri) present Opheliinae. c. Lateral segmental sensory pits present; the fascicles of setae sessile; body short and stout, grub-shaped Kesun, gen. nov. cc. No lateral segmental sensory pits; with distinct setigerous mamilae; body proportionately long and slender Tachytrypane Mcintosh. 66. Branchiae present. c. Branchiae pectinately branched; setae in preserved specimens not obvious (absent ?); anal cirrus single, proximally flattened Euzonvs Grube. cc. Branchiae not pectinately branched, unifiJamentous or rarely bifilamentous. d. Some or all of the setae serrulate. (Body with a longitudinal ventral furrow). e. All setae finely serrulate Caasandane Knberg. ee. Part of the setae smooth, part serrulate-spinous Niteiis Knberg. dd. Setae smooth or simply limbate. (With or without a ventral furrow). e. Body with a ventral furrow over all or part of length. /. Body rounded anteriorly, grooved ventrally posteriorly; parapodia well-developed, fascicles distinct, with mamilla between them. g. Branchiae simple, filiform; no anal plate; body not abruptly separated into a tho- racic and abdominal region Ophelia Savigny. gg. Branchiae all bifilamentous; an anal plate present; thorax sharply set off from abdo- men Thoracophelia Ehlers. //. Body grooved ventrally over entire length; parapodia often weakly developed and with the fascicles essentially single, or with the separation between notopodials and neuro- podials weak and not accompanied Ijy intervening mamilla. g. At the caudal end the body prolonged into a long, cylindrical or even somewhat clavate, tube at the tip of which is the anus, this tube usually finely furrowed transversely. h. Branchiae normally and uniformly developed over the entire or nearly the entire length; a distinct single median anal cirrus Omaria Grube. hh. Branchiae not uniformly developed. i. Branchiae very few, present only on the posterior median region; last pairs of setigerous processes not specially jirominent Ammotrypanella Mcintosh. n. Branchiae more numerous, absent from the median region but unusually strongly developed toward the ends; last (four) pairs of setigerous processes conspicu- ously sahent Urosiphon, gen. nov.' gg. Body not with a long cylindrical anal tube, the anal tube or scoop short. ' Genotype, Ammoirypane cylindrocaudatus Hansen, ovpd, tail, and aitJMi', a tube. KESUN. 385 h. Prostomium with a pronounced knob or boss on each side, the snout long and tapering, its terminal jjrocess distally enlarged hke a probe. Anliobactrum, gen. nov.' hh. Prostomium witli no such lateral bosses, simply conical, not thus prolonged, but sometimes bearing a stalked mucro. i. Pharynx with a fascia of elongate papillae on each side of the mouth. j. Setae smooth (branchiae lacking on first two and last two pairs of parapodia in type) Ladice Knberg. jj. Setae hmbate (branchiae on all parapodia-bearing somites). Terpsichore Kinberg. M. Pharjrnx not with such lateral fasciae of elongate papillae . . Ammotrypane Rathke. ee. Body without a midventral longitudinal furrow or a ventral sole. /. First setae borne on first complete ring caudad of mouth; setae partly smooth and partly serrulate-ciliate Dindymenides, nom. nov. //. First setae borne in front of mouth; setae all smooth Travisia Johnston. Synonymy of Genera. A considerable number of the genera in this family are very imperfectly known. Revisional work based upon plentiful material is much needed. In the tabulation I have taken up the known genera on such bases as the published accounts afford, though conscious of the slenderness of the basis of separation in several cases. It seems better to maintain genera established, rather than prematurely to merge them, until such time as om* knowledge concerning them shall permit fuller judgment and furnish evidence for better classification. The division into Polyopthalminae and Opheliinae is retained without expressing a personal opinion as to its naturalness. The tyi^e of Ophelina Oersted (1843), 0. acuminata Oersted, is identical with the type of Ammotrypane H. Rathke (1843), A. aulogaster H. Rathke. Hence the name cannot be used for a different generic group as is done by Hansen and also by Mcintosh for the genus Antiobactrum. Dindymene Kinberg, being preoccupied in the Crustacea (1847), is replaced by Dindymenides. Kesun, gen. nov.- Body short, pointed at both ends, fusiform or grub-like. Body rounded cylindrically, without ventral groove. Somites of the middle region triannulate, while the others may be only biannulate or entire. Prostomium smaU, wholly smooth and rounded, without processes. Parapodial tubercles small and smooth, or wholly absent. No cirri or ' Genotype, Ophelina brasilietisis Hansen. di-Taios in front, and fla.KTpov, a staff or rod. ^ Gosiute, ke, no, none, and sung, sun, lung or gill (pasun). 386 THE ANNELIDA POLYCHAETA. branchiae on any somites. No eyes. With a series of lateral sensory pits as in Travisia. Pygidium small, cylindrical, longitudinally fm-rowed. Segments not numerous (twenty-eight in the type). Genotype. — Kesun fusus, sp. nov. Separated from Travisia by the complete absence of cirri. Kesun fusus, sp. nov. Plate 67, fig. 5; Plate 68, fig. 1, 2. Body pointed at both ends, with the intervening region cylindrical, or sUghtly thicker anteriorly than posteriorly. The type is 14 nam. long with a maximum thickness of 2.5 mm. There are twenty-eight setigerous somites. The prostoinium is a small, wholly smooth process which is narrowed cephalad subconically, but is distally blunt. It is slightly compressed dorso- ventrally. (Plate 68, fig. 1). The peristomium strongly widening from the prostomium caudad. It is composed of three incomplete annuli. The surface is granular or finely vesicular, the vesicles being small and with those along the caudal edge largest. On each side there is the usual nuchal groove, this being deepest at its caudal end. (Plate 68, fig. 1). The second somite is biannulate. Each annulus bears a single row of fine but distinct vesicular papillae, with in front of this smaller and more or less obscure ones. (Plate 68, fig. 1). The succeeding somites to and including the fifteenth are triannulate. The sixteenth, seventeenth, and eighteenth somites are biannulate, the two latter incompletely so laterally. The remaining somites are uniannulate, or with two or three of the most anterior of them with vague indications of subdivision. All annuli with a single row of well-formed but very small papillae, the granules in front of this row smaller and inconspicuous. All the annuli of somites of the anterior and middle regions are very short. The undivided posterior somites are considerably longer than the annuli of the anterior somites, but are shorter than the entire somites. (Plate 68, fig. 2). Neither notopodial or neuropodial cirri or branchiae at all indicated on any of the segments. Fascicles of setae small, in two rows. On the anterior somites the fascicles arise from the apices of distinct processes, or papillae, of about the same size or TRAVISIA PROFUNDI. 387 but little higher than the neighboring ordinary papillae occurring elsewhere on the somites. These setigerous papillae decrease in size caudad, finally becoming wholly obliterated, and leaving the setae sessile, arising directly from slits in the body-surface. There are lateral sensory pits between the nem'opodia and notopodia on most somites, as in Travisia. (Plate 67, fig. 5). The pygidium is very small, short, and cylindrical, longitudinally weakly fiuTowed or canaliculate, and thus divided into twelve or fourteen inconspicuous lobes. Paler than the rest of the body. (Plate 68, fig. 2). Locality. Toward the Marquesas: Sta. 3684 (lat. 0° 60' N., long. 137° 54' W.). Depth 2,463 fms. Bottom of greyish-yellow Globigerina ooze. 10 September, 1899. One specimen. Travisia Johnston. Ann. nat. hist., 1S40, 4, p. 373; Grube, Fam. annel., 1851, p. 71; Sitz. Schlesch. gesellsch., 1868, p. 6; McIktosh, British annelids, 1915, 3, pt. 1, p. 25. Travisia profundi, sp. nov. Plate 67, fig. 1-4. The color of the preserved animal is grey throughout. The body is pointed at both ends, subfusiform, though conspicuously broadest in front of the middle, being broadest and decidedly deepest at about one third the distance from the anterior end. The dorsal surface strongly convex, the ventral more weakly so, but not truly flattened and not at all fur- rowed. The type is 27 mm. long and, at the thickest region, 5.25 mm. wide and 6 mm. deep. (Plate 67, fig. 1). The prostomium is a very small and bluntly rounded organ which is wholly smooth. (Plate 67, fig. 1, 2). The second somite widens strongly caudad like the frustum of a cone. It is distinctly biannular and is crossed longitudinally on each side at the dorso- lateral level by the nuchal groove, which terminates anteriorly at the prostomium. The annuU are covered densely with contiguous, nodular, pustule-like papillae, of which there are five or six transverse rows on the first and fom* or five on the second. The first of these two annuli on the ventral side is deeply notched caudally, bordering the mouth in front and anteriorly at the sides, while the mouth completely divides the second annulus ventrally, its ends thus forming the remaining part of the lateral borders of the mouth. (Plate 67, fig. 2). 388 THE ANNELIDA POLYCHAETA. The succeeding somite, i.e., the second, is also biannular. Each annulus with a single transverse row of low, rounded papillae along the caudal border, with cephalad of this smaller papillae like those of the preceding somite, with the integument between the annuli proper appearing somewhat tesselated. The second annulus of the second somite is incomplete laterally and the first is deeply grooved ventrally where it borders the mouth on its caudal side. On each side of this somite between the two fascicles of setae is a sensory pit, the mouth of which is vertically lenticular in form. The third somite is triannulate, with the third annulus indistinct laterally. Papillae and integvmient as in the preceding somite. The following somites to and includhig the fourteenth are similarly triannulate in form, with papillae and mtegument the same. The fifteenth segment is incompletely triannulate, the two more caudal annuli being indistinguishable from each other laterally. The sixteenth and seventeenth somites are biannular, and the remaining somites are entire, or uniannular, with the annuli distmctly and abruptly larger than those of the preceding somites and with correspondingly more numerous, large, vesicular papillae, the papUlae decreasing in size from the caudal edge cephalad to the interannular tesselated integument. The papillae are absent along the sides from a level a little above the upper setae to one a little below the lower ones, giving the effect of a longi- tudinal fmTow along each side of the body, with the papillae above and below the groove large. (Plate 67, fig. 1). The branchiae fii'st appear on the third somite and occiu" on each one there- after to and including the fom'teenth, but are quite absent from all others. Each branchia is subfiliform, proximally subcyhndrical, gradually narrowing distad, conically aciuninate at tip; strongly transversely wrinkled. (Plate 67, fig. 1, 3). Those of the sixth to twelfth (Plate 67, fig. 4) somites longest, those of the fourteenth very short, with the thirteenth intermediate and the most anterior ones also very small. The longest ones m the preserved specimens do not exceed the length of the somite. Each branchia is inserted above the lateral sensory pit close to the notopodial setae on the thud, or on the fused second and third, annulus of the somite. The setae occiu- on somites from the second inclusive caudad. They arise from pits with sUt-hke openings into which they are apparently more or less retractile. (Plate 67, fig. 3, 4). They are pale, very fine, capillary forms of varying length, those of the notopodial tufts longer than the ventrals, as usual. Pygidium short, conicocyUndiical, truncate distad, divided by longitudinal sulci into ten or eleven lobes in the usual manner. (Plate 67, fig. 1). SCALIBREGMIDAE. 389 Locality. Off Peru : 1 1 1 miles N. W. of Aguja Point. Sta. 4651 (lat. 5° 42' S., long. 83° W.). Depth 2,222 fms. 11 November, 1904. One specimen. Travisia olens Ehlers, occurring in the Strait of Magellan, is a larger, more evenly fusiform species having thirty-one setigerous somites instead of only twenty-sLx in the present species. It has branchiae over practically the entire length, whereas in profundi these do not occm' caudad of the fom'teenth somite. Similarly T. pupa Moore, which is close to olens, is a much larger species, con- sisting of thirty-one or thirty-two somites, in which the branchiae likewise occur on all somites from the thii'd to near the caudal end of the body. The annula- tion of the somites in this form is conspicuously different. SCALIBREGMIDAE . In this family the body is comparatively short, sometimes enlarged anteriorly, maggot-like in form, or fusiform. A very thin cuticle invests the thick granular hypoderm in such a way that the skin appears roughened or tesselated, especially anteriorly, in a characteristic manner. The color is often dull brick-red. The prostomium is small, either with or without anterolateral, tentacle-like, prolongations; when the tentacles are absent the prostomium simply divided by a fuiTow into two rounded lobes. Eyes none, or so-called ocular bands present (Sclerocheilus) . On each side a groove thi'ough ^^hich the nuchal organ may be everted. The somites are distinctly annulated. In most species between the rami of each parapodium there is a small sense-organ which is retractile. The parapodia are biramous, with notopodia and neuropodia equally developed, in some with protruding setigerous papillae not evident, the setiger- ous fasciae sessile, in others with the processes prominent. The setae in general of two types, simple capillary setae and fm'cate setae with somewhat unequal, commonly barbed, branches. In addition, there may be present in the most anterior one to three setigerous somites setae of a much stouter, acicular type. Branchiae either present or absent, when present confined to the fu'st five or six somites and commonly beginning on the second. Anal cirri either present or absent. A pair of nephridia in each of the somites excepting a few of the most ante- rior. Each is a narrow ciliated tubule with internal funnel small and open. Dioecious, with the gonads inicroscopic in size. Pharynx eversible and whoUy smooth. 390 THE ANNELIDA POLYCHAETA. Sometimes occurring between tide-marks and in shallow water, but perhaps most coimnonly to be secm'ed by dredging, being found down to depths of 700 and 800 fms. They burrow in the sand and mud, in which they may penetrate to a depth of one or two feet. The habits in general, at least in the case of the best known form, Scalibregma inflatum, are much like those of the lugworm, or Arenicola. They are limivorous. In the intestine (e.g., of Polyphysia jeffreysi) is found sand and mud, in which occur fragments of Foraminifera, Radiolaria, diatoms, sponge-spicules, crustaceans, and other organisms. Known from the temperate seas of both hemispheres and from the cold waters off northern Em-ope. In general the members of the family are poorly known as to their detailed anatomy, variations, and development. Key to Genera. a. Prostomium with anterolateral tentacular processes. 6. Parapodia of somites behind the twelfth or fifteenth projecting prominently at right angles to the body, each forming a laminate appendage bearing a dorsal and a ventral cirrus. c. Branchiae present on the anterior somites Scalibregma H. Rathke. cc. No branchiae present Pseudoscalibregma Ashworth. 66. Parapodia not forming laminate appendages; no dorsal cirri; ventral cirri either absent or else present in the posterior region alone and digitiform. c. Stout acicular setae present on the first setigerous somite and sometimes also on the two fol- lowing. d. With pigmented ocular bands; ventral cirri present in the posterior region; acicular setae present on the first setigerous somite only Sclerochcilus Grube. dd. With no ocular bands; no ventral cirri; acicular setae on the first three setigerous somites, e. First three pairs of parapodia greatly exceeding the others in size, elliptic in outUne, and much more widely separated; with a conspicuous anal tube abruptly much narrower than the body, with marginal papillae, but no anal cirri; acicular setae stout, conspicu- ous Givasitoa, gen. nov.' ee. Plrst three pairs of parapodia not thus strongly differing; with 5 slender anal cirri, no such conspicuous anal tube; acicular setae reduced, more slender. Asclerocheihis Ashworth. cc. No stout acicular setae on any of the somites; no cirri; an abruptly narrower, cylindrical anal tube Kebuita, gen. nov.' aa. Prostomium with no anterolateral tentacular processes; divided by a median groove with each half simply rounded. 6. Four (or si.\) pairs of branchiae present on somites II-V Polyphysia Quatrefages. 66. No branchiae present Ldpobranchius Cimningham and Ramage. This key represents the classification developed by Ashworth (Quart, joiu-n. micr. sci., 1902, 45, p. 237-309, pi. 13-15) in his excellent study of Scali- bregma and its affinities. Synonymy of Genera. Eumenia Oersted (1843) is preoccupied in the Lepidoptera (God., 1825) as well as by a phyllodocid genus of Risso. Hence I adopt here Polyphysia ' Genotype, Oncoscolex heterochaetus Augener. Gosiute, g^vasi, tail, and toa, tube. -Genotype, Eumenia glabra Ehlers. Gosiute, ke, no, and bui, eye. SCALIBREGMA. 391 Quatrefages, proposed as a substitute in 1865, l)ut not used by subsequent workers. Ashworth in discussing {Op. cit., p. 292) the Eumenia glabra Elilers, here estabUshed as the type of a new genus Kebuita, concludes that it stands apart in ha\'ing the skin smooth and in that it "bears no signs of secondary annulation." However, upon reexamination of Ehlers's type I find that the skin in the anterior region and dorsally is strongly tesselated in the manner prevalent in the family and that the somites are distinctly annulated, as usual. Ashworth judges, as he says, from Ehlers's figure, which is inaccurate in respect to these features. The Oncoscolex {Eumenia) heterochaetus of Augener (Bull. M. C. Z., 1906, 43, p. 159, pi. 6, fig. 110-112), di-edged by the Blake near St. Vincent, W. I., is not properly referred to Oncoscolex, a dubious genus apparently pertaining rather to the Capitellidae. Augener thinks his species possibly identical with Ehlers's glabra because of a general superficial resemblance; but the two forms are widely different, the conspicuous stout acicular blades of the first thi'ee somites and the conspicuously enlarged anterior parapodia of heterochaeta obviously separating it from the other species. In having the. stouter setae on the first three setigerous somites heterochaeta is like the species named by St. Joseph (Ann. sci. nat., 1894, ser. 5, 17, p. 113, pi. 5, fig. 146, 147) Lipobranchius intermedius and by Ashworth made the type of Asclerocheilus. I have not seen a specimen of intermedius; but relying upon St. Joseph's description and his statement that aside from the absence of eyes and ventral cirri, and certain differences in the segmental organs, ova, etc., "sous tons les autres rapports, 1. L. intermedius est absolument semblable au S. minutus [Schlerocheilus]," I believe that species is not congeneric with heterochaeta, the type of which I have reex- mined and for the latter proposed the new genus Gwasitoa. Nevaya Mcintosh (Ann. mag. nat. hist., 1911, ser. 8, 7, p. 149, pi. 5, f.l- Ih) is a somewhat enigmatic form placed in relationship to Schleh-ocheilus by its author. But it has no frontal processes, and in the key would be included in Lipobranchus, as it "apparently has no branchiae. It possesses a strongly marked dorsal caruncle and has no bifid setae; a fully developed parapodium, with normal setae, in front of the somite (second) bearing the stout acicular setae. ScALiBREGMA H. Rathke. Nova acta Acad. Leop.-Car., 1843, 20, p. 184; Ashworth, Quart, journ. micros, sci., 1902, 46, p. 242, 296; McIntosh, British annelids, 1915, 3, pt. 1, p. 33. Oligobranchus Sars, Fauna litt. Norveg., 1846, 1, p. 91. 392 THE ANNELIDA POLYCHAETA. SCALIBREGMA INFLATUM H. Rathke. Nova acta Acad. Leop.-Car., 1843, 20, p. 184, pi. 9, fig. 15-21; Ashworth, Quart, journ. micros, sci., 1902, 45, p. 238. OKgobrarwhus roseus Sabs, Fauna litt. Norveg. 1846, 1, p. 91, pi. 10, fig. 20-27. Oligohranchus (,roerdandicus Sars, Ihid., p. 92. Scalibregma roseum Sars, Nyt mag. naturv., 1853, 7, p. 381. i^calibregma inflatum coretlmsa Michaelsen, Gronland Annel., 1898, p. 127 (epitoke). Locality. Between Unalaska and Kadiak: Sta. 3337 (lat. 53° 55' 30" N., long. 163° 26' W.). Depth 280 fms. Bottom t'emp. 39.3° F. 27 August, 1890. One specimen. This is a widespread species occurring on both sides of the Atlantic in north- ern latitudes, and also in the northern Pacific, as well as in the far southern lati- tudes, such as the region about Prince Edward Island, Kerguelen, Strait of Magellan, and New Zealand. . Arenicolidae. In these annelids the body is elongate and cyUndrical, is composed of numer- ous somites, and presents either two or three more or less distinct regions. Colors commonly greens or reds, with often superficial iridescence. The skin is charac- teristically tesselated, consisting of a thin cuticle covering a thick glandular hypoderm. Prostomium small, or but moderately developed. Nuchal grooves posteri- orly. No tentacles or palpi. Eyes primitive and indistinct. The peristomium in most species bears a pair of otocysts. It is fused with a somite that early becomes achaetous. In the setigerous region of the body each soinite, excepting the first thi-ee, is composed of five distinct annuU excepting in Branchiomaldane, in which but two annuli are found. • The parapodia are obviously biramous, each presenting a conical noto- podium bearing ordinary setae and a transversely thickened neuropodium bear- ing crochets. Branchiae always absent from the first seven somites, and often from more. They are highly characteristic structures attached dorsally just mesad of the bases of the notopodia. Each is a hollow outgrowth which is highly branched in either a dendritic or pinnate manner, or the branches radiating from a common point like the ribs of a fan. The gills often more or less retractile. Setae of the notopodia are all of the simple capillary type, smooth proxi- AREXICOLIDAE. 393 mally, but distally bearing short, hair-like teeth, or processes, along the sides. In young specunens a second type of notopodial seta may occur, this being limbate, with an exceedingly fine tip. The neuropodial setae are stout crochets which are more or less cu^-ved and present a rostrate enlargement distally, which ordinarily shows teeth along the distal edge and may or may not exhibit a small subrostral spine suggesting the more prominent one, or the corresponding tuft of hair, occurring in those of the Maldanidae. Five, six, or thii'teen pairs of nephridia are present. In these there is the usual open cihated nephrostome internally. There are one or more pairs of glandular caeca opening into the posterior portion of the oesophagus. The pharynx is globular. It is unarmed, though it may have papUlae tipped with chitin. Gamble and Ashworth give an excellent general account of the family. (Quart, journ. micr. sci., 1900, 43, p. 419-569, pi. 22-29). The members of this group are more or less confined to shallow water. They normally occur in and above the Laminarian zone. They frequent sand and gravel in which they bm-row, though the young forms are often found among Algae rather than in the sand. The tubes of Arenicola marina, are U-shaped and are stained on the inner side from the abundant yellowish green mucus exuded by the skin. Speaking of A . cristata as observed by him at Charleston Harbor, Stimpson saj^s: "It occurred in the third and fourth subregions of the httoral zone, living in holes in the hard sand, which it had excavated to a length of two feet. These holes were exactly adapted in width to the thickness of the animal, and were not furnished mth a lining of any kind. Thej^ extended obliquely downward, being at first perpendicular, but curving so as to become almost horizontal; the lower extremity was about one foot below the surface . . .' . All the specimens were found in their holes, with the anterior extremity downward, and when taken were trying to escape by digging still fm'ther into the sand, which is effected by continued rapid evolutions of the proboscis .... Dm-ing the latter part of March, we frequently observed in and about the holes of these worms great quantities of a soft, transparent jelly, filled with minute brownish specks, which proved to be eggs." (Proc. Boston soc. nat. hist., 1855, 5, p. 116.) The arenicolids are limivorous. The spiral castings are to be seen on the surface near the openings of their burrows. Branchiomaldane uincenti, a small form only 8-20 mm. long, fives in transparent mucus tubes attached to calcareous Algae at the Canary Islands and in the English Channel. 394 THE ANNELIDA POLYCHAETA. Savigny used the term Telethusa for this family, which is still often referred to as the Telethusae, or the Telethusidae. Key to Genera. %. Branchiae appearing only in the posterior region (somite 18-21); simple, bifid, trifid or quadrifid; hermaphroditic; otocysts absent Branchiomaldane Langerhans. J. Brancliiae beginning in the anterior region, branching more complex; dioecious; otocysts usually present, but in some absent. b. A distinct tail present, the parapodia and branchiae not extending to the caudal end of the body; prostomium well developed, trilobed; branchiae pinnate, eleven to thirteen pairs, the first ones appearing on the seventh setigerous somite Arenicola Lamarck. bb. No distinct tail, the parapodia and branchiae being continued to the caudal end of the body; prostomium simple and non-lobate; branchiae unilaterally branched, of variable number, the first ones appearing farther back on setigerous somite 12-16 Arenicolides Mesnil. Akenicola Lamarck. Anim. s. verteb., 1801, 5, p. 324; Gamble and Ashworth, Quart, journ. micr. sci., 1900, 43, p. 540. Chwizobranchii^ Quatrefageh, Hist. nat. anneles, 1865, 2, p. 267. Clymenides Clapar^de, Beobacht. anat. ent. wirbell. thiere, 1863, p. 30. Pteroscolex Lutken, Vid. meddel. naturk. foren Kjobenh., 1864, p. 120. Arenicola ceistata Stimpson. Proc. Boston soc. nat. hist., 1855, 6, p. 114; G-^mble and Ashworth, Quart, journ. micros, sci., 1900, 43, p. 432. Arenicola {Pteroscolex) antillensis Lvtken, Vid. meddel. naturk. foreu Kjobenh., 1864, p. 120. Arenicola antillensis Ehlers, Mem. M. C. Z., 1887, 15, p. 173. Locality. Florida. Albatross, 1886. One large specimen conforming fully to this species, which occurs along the south Atlantic Coast of the United States and in the Antilles, and has been taken as well at Naples. Flabelligeridae . In the members of this family the body is short, rarely exceeding seven or eight centimeters in length, with the number of somites mostly limited, rarely as many as ninety. The thickness of the body varies, but the general form is commonly fusiform, or more swollen anteriorly. The surface of the body is mostly covered with muciparous papillae, which are sometimes filamentous and at others clavate, with commonly a transparent coating of mucus, to which grains of sand adhere. This mucus when fresh, i.e., the outer layers of it, is soluble in 5-10 per cent sodium carbonate, but not so the older, inner and col- loidal layers. (Bles, Rept. Brit, assoc. 1892, 1891, p. 373). FLABELLIGERIDAE. 395 The prostomivun is small and often retracted into the peristomium. It bears a pair of palpi, which are in general grooved. Above, the tentacles or branchiae are short and filiform, and more or less numerous, always four or more, these extending forward about the prostomium and palpi. Eyes nor- mally four, though easily overlooked because of the frequent retraction of the prostomium. The peristomium is generally short, but it may be extended into a short and retractUe tube. It is setigerous. The parapodia are bu-amous, with setigerous papillae usually absent or obsolete, but sometimes distinct. No true cirri. The setae are all characteristically strongly cross-striate, or annulated. They are of two principal types, slender capillary ones, and shorter, stout acicular ones, or crochets. The capillary setae are always sunple; the crochets either simple or composite. The bristles of the first few somites in most cases are very long and directed forwards so as to form the so-caUed cage about the ante- rior end; these setae often have a special structure and a characteristic iridescence. The neplii-icha are two tubes ending each in a cul-de-sac near the sides of the stomach and opening separately or by a common pore anteriorly near the mouth (Haswell, Proc. Linn. soc. N. S. W., 1892, ser. 2, 6, p. 349). The blood-fluid when seen in thin layers, or as it appears in the animals in life, is green, the color being due to a substance allied to haemoglobin and termed chlorocruorin. In quantity it is dark red. In alcohol, the blood commonly appears redcUsh.^ The aluuentary tract presents anteriorly a narrow oesophagus with cihated hning, behind this a wide, thin-walled stomach, with an anteriorly projecting coecum, followed by a narrow, thick-waUed intestine, in wliich there is normally a more or less strongly marked sigmoidal flexure. The flabelligerids Uve largely in muddy ground, or muddy sand, and in slime, at various though mostly small or moderate depths. They may occiu" between tide-marks on the one hand, while they may descend to great depths on the other, the remarkable Buskiella of the Challenger expedition occurring at a depth of 2,500 fms. (Mcintosh, Challenger AnneUda, 1885, p. 372). The httoral forms are dominantly inhabitants of the colder regions. Thus, as Ehlers points out (Festsch. K. gesellsch. Gottingen, 1901, p. 179), of the nine species mentioned by Levinsen (Vidensk. meddel. foren. Kjoben., 1883, p 301) in his review of the flabelligerids of the North Sea, six are Ai-ctic. Cams gives ' CJ. Lankester, Proc. Royal Soc, 1873, 21, p. 2; Mcintosh, British anneUds, 1915, 3, pt. 1, p. 85. 396 THE ANNELIDA POLYCHAETA. but three species from the Mediterranean; Grube in Semper's extensive collec- tion from the Phihppines found but one species of this family; Gravier lists one from the Red Sea ; and Ehlers lists three species from the Magellan Strait, and one from the coast of Chile. Willey notes but one from Ceylon, Augener one from southwest Australia, and Izuka none from Japan. Professor Haswell mentions three from New South Wales. Of the five species secured by the Albatross, one is from the Alaskan region, one from the Atlantic coast of the United States, and the others from off Mexico and Panama, but at depths of from 493 to 1,879 fms. The flabelligerids swallow the muddy sand in which they live. In this material, when taken from their ahmentary tracts, are found diatoms, shells of Radiolaria and Foraminifera, spicules of sponges, spines of such .forms as Spa- tangus, fragments of Algae and other organic debris. Some are commensals, such as Flabelligera commensalis Moore, which occurs among the spines of Strongy- locentrotus purpuratus in Monterey Bay (Moore, Proc. Acad. nat. sci. Philad., 1909, p. 288). They frequentty themselves bear parasites attached to then- setae, such as certain Fungi and stalked Infusoria, e.g., Vorticellae and Carche- sium. Internal parasites are also known, e.g., the peculiar crustacean parasite {Bradophyla pygmaea) found by Levinsen in the anterior part of the alimentary canal of Brada villosa. Key to Genera. a. Branchiae and tentacles borne on one or two conspicuous jirolongations or stalks. 6. Branchiae arising from a single protrusible stalk Zorus Webster and Benedict. 66. Branchiae borne on two club-shaped or conical stalks. c. Composite neuropodial setae present; branchiferous stalks conical Piromis Kinberg. cc. Setae all simple; branchiferous stalks club-shaped Coppingeria Haswell. aa. Branchiae and tentacles not borne on stalks, or at most a moderate prominence bearing but part of the branchiae. 6. Bearing dorsally a conspicuous median, tentaculiform process, with a smaller lateral one each side just caudad of the mouth opening (occurring at great depths) Buskidla Mcintosh. 66. With no such median dorsal appendage. c. Bristles of first two somites fine, in length and structure but little different from the rest, not forming a distinct "cage"; a pair of distinct genital papillae between the fourth and fifth setigerous somites Brada Stimpson. cc. Bristles of the first and generally also of the second and third somites mostly decidedly longer and stouter than the others, commonly directed forwards and forming a "cage"; no genital papillae between the fourth and fifth setigerous somites. d. Body densely covered with long, filamentous, or hair-Uke papillae. e. Notopodial setae all capillary and smooth. /. Neuropodial setae in form of short, stout, hooked crochets; numerous branchial filaments on each side of head; anterior setae forming a distinct "cage". . . .Flabelligera Sars. //. Neuropodial setae numerous, very long and stout, not crochet-formed ; not with numer- ous branchial filaments each side of head; anterior setae not forming a distinct "cage"; body very broad in proportion to length Ilyphagus, gen. nov. FLABELLIGERIDAE. 397 ee. Notopodial setae in part capillary and finely biserrate, or plumose, and in part bidentate crochets Pantoithrix, gen. nov.' dd. Papillae not filamentous and dense, mostly shorter, coarser, and fe%^er, and sometimes sparse and inconspicuous. e. Setae all capillary in both neuropodia and notopodia, or rarely a few small crochets in a few of most caudal somites only. Branchiae few, definite, typically eight in number, with four long and four short, elevated above the tentacles Saphohranchia, gen. nov.^ ee. Crochets present in the neuropodia, or in all excepting the most anterior. /. Crochets on certain somites (in the genotype V-VIII) composite. Conspicuously constricted between the second and third setigerous somites. TherocJiaeta, gen. nov.' //. Crochets all simple. g. Crochets with a distinct subapical spur or spine. Branchiae numerous, in a U-shaped group Balanochaeta, gen. nov.* gg. Crochets all with tips entire, no spur or subapical process. h. Branchiae eight or ten arranged in two equal and parallel rows, one behind the other and caudad of tentacles Flemingia Johnston.^ hh. Brancliiae numerous, short and equal. i. Borne upon the anterior surface of a membranous lobe vertically elevated caudad of the tentacles Semiodera, gen. nov." ii. Borne upon the edge of a membranous rim in a U-shaped group. Stylariodes DeUe Chiaji.' Synonymy of Genera. In tliis tabulation of genera it has been impossible to make sure that all species that have been described are included, because of the meagreness of many accounts. However, it has seemed best so far as possible to break up the mani- festly heterogeneous assemblage of species that have been accumulated under Stylarioides along Unes suggested by Marenzeller and St. Joseph, since accumu- lating evidence shows that these groups are natural as well as convenient. Reexamination is necessary to remove all doubt as to the status of Zorus Webster and BenecUct. The name Trophonia is still often used either in the same sense as Stylari- oides, or to designate a different but closely related group of species. The name, however, cannot be used since T. barbata Audouin and Milne Edwards (Cuvier) , its type-species, is a synonym of S. moniliferus Delle Chiaji, the type of Stylari- oides. Pherusa Oken, from which the family has sometimes been called the Pherusidae, cannot be used for this genus because the name is preoccupied in the Crustacea. ' Genotype, Pherusa chilensis Schmarda. Trac/oios, of all sorts, and 9pi|, hair. - Genotype, Stylarioides longisetosa Marenzeller. aaii%, distinct, definite, and ppdyxi-a, gill. 'Genoty'pe, Stylarioides collarifer Ehlers. daipos hinge, articulation, and x"''"'!, seta. ■•Genotype, Trophonia eruca Claparede. paXavos, a clasp or snap, and xairi?, seta. ^ Genotype, F. muricata Johnston (F. plumofia Miiller). 'Genotype, Siphonostoma cariboum Grube. a-qfiaia, a standard, and &ipri, neck. ' Genotype, S. monilijerus Delle Chiaji. 398 THE ANNELIDA POLYCHAETA. Flabelligera Sars. Bidrag til Soedyr. nat., 1829, 1, p. 31. Siphostoma Otto, Nova acta Acad. Caes. Leop. nat. curios., 1820; Cuvier, Regne anim., ed. 3, 1830, 3, p. 196 {nom preocc). Chloraema Ddjardin, Ann. sci. nat., 1839, ser. 2, 11, p. 288. Siplwnostomum Grube, Actin. ecliin. wiinner Mittelmcere, 1840, p. 68; Rathke, Nova acta Acad. Leop.- Car., 1843, 20, p. 208. Sipho7instoma L^VCKAUT, Archiv naturg., 1849, 15, p. 164 (worn preocc). LopMocephalus Costa, Ann. sci. nat., 1841, 16, p. 276. Teclurella Stimpson, Invertb. Grand Manan, 1853, p. 32, pi. 3, fig. 21. Chloraemum Sars, Nyt mag. naturv., 1873, 19, p. 247. Flabelligera infundibularis Johnson. Proc. Boston soc. nat. hist., 1901, 29, p. 417, pi. 12, fig. 124-127. The specimens referred to this species are in a bad state of preservation, but they seem to conform to the description in so far as the characters can be made out. The species was found originally in Scow Bay, in the Puget Sound region, where it was abundant. "This worm seemed to occur in a layer along the somewhat muddy bottom, for bushels of this jelly-like mass exclusively were brought up from a region half an acre in extent " (Harrington and Griffin, Trans. N. Y. acad. sci., 1897, 29, p. 162). Some of the Scow Bay specimens came from a depth of not more than six fathoms, but data on others were lacking. The Alaskan specimens here recorded came from a greater depth. Their long black- tipped ventral hooks and the long pedicillate papillae are conspicuous features. Locality. Between Unalaska and Kachak: Sta. 3337 (lat. 53° 55' 30" N., long. 163° 26' W.). Depth 280 fms. Bottom of green mud and rock. Bot- tom temp. 39.3° F. Two specimens di-edged 27 August, 1890. They are at present free from any enclosing jelly-hke mass. Flabelligera affinis M. Sars. Bidrag. til Soedyr. nat., 1S29, 1, p. 31, pi. 3, fig. 16; McInto^h, Brit, annelids, 1915, 3, pt. 1, p. 107. Chloraema edwardsii Dujardin, Ann. sci. nat., 1839, ser. 2, 11, p. 288, pi. 7, fig. 1-6. Siphonostomum papillosum Grube, Actin. echin. wiirmer Mittelmeere, 1840, p. 68. LopMocephalus edwardsii Co.sta, Ann. sci. nat., 1841, 16, p. 276. Siphonostomum vaginiferuni , Rathke, Nova acta Acad. Leop.-Car., 1843, 20, p. 211, pi. 11, fig. 3-10. Siphonostoma uncinala Milne Edwards, Cuvier's Rogne anim. Anncl., 1843, p. 27, pi. 6, fig. 4, 4a. Siphonosloma mginifera Leuckart, Archiv naturg., 1849, 15, p. 164. Chloraema dujardini Quatrefages, Ann. sci. nat., 1849, ser. 3, 12, p. 282, pi. 9, fig. 1-9. Chloraema sordidwn Quatrefages, Ibid., 1849, ser. 3, 12, p. 285, pi. 9, fig. 10. Siphonostoma gelatinosa Dalyell, Pow. creat., 1853, 2, p. 256, pi. IS, fig. 10-12. Tecturella jlaccida Stimpson, Invertb. Grand Manan, 1853, p. 32, pi. 3, fig. 21. Siphonostomum diplochailos Kolliker, Kurz. bericht., p. 10, 17, pi. 6, fig. 7. Chloraemum pellucidum Sars, Nyt mag. naturv., 1873, 19, p. 247. Siphcmostomum gelatinosum Gibson, Proc. Lit. philos. soc. Liverpool, 1886, 40, p. 158. BRADA \'ERRUCOSA. 399 Locality. Atlantic Coast: Between Cape Hatteras and Nantucket. Sta. 2291 (lat. 35° 25' 30" N., long. 75° 20' 30" W.). Bottom of broken shell and grey sand. Depth 15 fms. 20 October, 1884. Two specimens. This species is common on the North Atlantic Coasts of Europe and .America, where it is often found between tide-marks. It also occurs in the Bering Sea and American Coast of the Northern Pacific. Brada Stimpson. Invertl). Grand Manan, 1853, p. 32; McIntosh, British annelids, 1915, 3, pt. 1, p. 103. Brada verrucosa, sp. nov.^ Plate 68, fig. 3-6. Body subclavate, being widest at about one fourth the length from the anterior end, and then narrowing conspicuously into a slender posterior region. Most slender a Uttle distance in front of the caudal end, which may be somewhat spatulate. One specimen 60 mm. long has a maximum width of 6.5 mm. and a minimum diameter in the posterior region of 2.5 mm. The segments in the anterior and middle regions of the body do not vary much in length, but in the caudal fifth, or thereabouts, they decrease decidedly caudad and at the end are very short and crowded. The dorsal surface is strongly convex, as usual, while the ventral is complanate and over the caudal nine or ten somites marked by a distinct median longitudinal gi'oove. Somites forty-nine to fifty-two. The maximum length in the type-specimens is about 80 mm. The prostomial region is retracted in the usual way, leaving the common trifid opening, projecting from which in some specimens may be seen the tips of the tentacles and palpi. The palpi are rather narrow, sublanceolate, contracting to a narrowly rounded tip; dorsal surface smooth; ventraUy with the usual median longitudinal furrow, the surface on each side of this being transversely folded or \\Tinkled. (Plate 68, fig. 3). The tentacles are slender, filiform, a considerable number on each side, though it was impossible to determme the number accurately. The papillae of dorsal surface high and stout, subcorneal, apically rounded and hard, as in B. mammilata Grube. They are not arranged in regular longi- tudinal series. In the anterior and middle region the tubercles are mostly in ' verrucosus, covered with warts. 400 , ■ THE ANNELIDA POLYCHAETA. two, or, less commonly, three, irregular transverse rows on each segment, becom- ing fewer caudad, there being on somites toward the caudal end usually but one transverse row. The tubercles are highest and most crowded in the widest region of the body, becoming lowest and s]:)arsest in the caudal region. There are no tubercles on the sides of the body between the parapodia. The venter is also wholly smooth. Neuropodial setae somewhat reddish brown, inserted in a prominent tuber- cle, the fascicle usually consisting of four setae. These setae are relatively short, being shorter than the somite to which they pertain, and the most ventral one commonlj' abrupth' shorter than the adjacent one, the others ordinarily differing but httle, or decreasing a little from the most dorsal ventrad. They are straight, or but slightly curving distally. AnnuU of setae moderate in length, shortest proximally, often a longer annulus occiu-ring at intervals between those of ordinary length. (Plate 68, fig. 4). Notopodial setae pale, much longer and much more slender than the neuropodials, straight, or a little curving in the very fine distal region. Annuli long, longest at the distal end, as shown in the figures. (Plate 68, fig. 5, 6). Locality. Off Mexico: Sta. 3417 (lat. 16° 32' N., long. 99° 48' W.). Depth 493 fms. Bottom of green mud. 11 April, 1891. This species suggests B. mammilata Grube, occurring at Kerguelen and other far southern localities. The present species is a larger form, with more numerous segments and larger dorsal papillae. The neuropodial setae are fewer in a fascicle, relatively shorter, with annuli conspicuously longer. Brada irenaia, sp. nov.^ Plate 68, fig. 7-9; Plate 69, fig. 1-3. Body consisting of forty or forty-one setigerous somites. The type-speci- men, in which the prostomium is extended, is narrowest anteriorly, a little constricted at the second and third somite, then widening gradually to about the twelfth setigerous somite, remaining then of uniform width, or narrowing but Uttle, to about the thirty third somite, from where it narrows moderately to the rounded caudal end. Segments of median region longest. Dorsal surface strongly convexly arched. Ventral surface between parapodia flattened, more strongly so caudad, and over the caudal third of length showing a median longi- tudinal furrow. Total length, about 44 mm. Greatest width, near 5 mm. ' (ipriiioLOi, pacific. BRADA IRENAIA. 401 The palpi are short, flattened and broad, widest above base and narrowing to the tip, oblong-ovate. With the usual distinct longitudinal groove along the ventral surface from base to tip. The tentacles have been so far rubbed off that their number could not be ascertained. The mouth in the extended condition of the prostomium shows as an arcuate sUt, the two halves of the bow being concave ventrally; the hning membrane somewhat ridged or \\Tinkled. Dorsal surface densely papillose, the papillae in the present contracted condition touching each other, or nearly so. There are mostly from thi-ee to fi\'e of these in the length of a somite. Wlien extended the papillae appear to be elongate, conical, or more or less flattened in the anterocaudal direction. Ventral surface similarly with numerous papillae, which when extended are in part elongate and more or less filiform. Sides also equally densely papillose between the parapodia. Both neuropodial and notopodial setae in the median region are relatively long and in conspicuous tufts borne each on a well-developed tubercle. The notopodial setae are decidedly more slender than the neuropodials, though not much differing in length. They are very fine distally, where they are curved, often uncinately so. They are annulate throughout their length, excepting the fine tip. They are finer and more curved on the anterior somites. The annuU are decidedly longer at the base than in B. villosa, increasing in length distad as shown in the figiu-es. (Plate 68, fig. 7-9). Neuropodial setae stout and straight, ending in a transparent, abruptly more slender tip. Setae below, or proximad of, tip strongly annulate. The annuh unifoim or shorter distad, all relatively broader and shorter than those of the notopodials. (Plate 69, fig. 1-3). Setae , mostly five to eight in a fascicle. Genital papillae between foiu-th and fifth somites elongate, slenderly sub- conical. Locality. Off Panama: Sta. 3382 (lat. 6° 21' N., long. 80° 41' W.). Depth 1,793 fms. Bottom of green mud. 7 March, 1891. One specimen. This species seems to be near B. villosa (Rathke), a form occiuring widely in the North Atlantic and Arctic regions and also recorded from the North Pacific. A comparison with a specimen of villosa from Spitzbergen, however, shows the forms to be clearly distinct in the character of the setae. In the middle segments of the present species the neuropodial and notopodial setae are more nearly of the same length, and the notopodials are proportionately stouter. The neuropodials are decidedly longer in relation to the length and breadth of the somites. A very conspicuous difference is the decidedly gi-eater length of the annuU in the setae. 402 THE ANNELIDA POLYCHAETA. Ilyphagus, gen. nov.^ Body broad in comparison with length, rounded at both ends, at neither of which it is otherwise much attenuated. Characters of prostomium unknown. Parapodia bu-amous, without obvious setigerous prominences. Setae all simple, strongly cross-striate, or annulated, as usual. Those of the notopodial fascicles capillary, very fine, uniform. Those of the neuropodia very much coarser, straight, or nearly so, long, narrowing to a fine tip, not in crochet-form. The setae of the most anterior somites not specially elongate and not forming a "cage." The surface of the body densely clothed with hair-like filaments, more or less uniformly arranged, and completely cloaking the body. Integument non- tuberculate. Genotype. — /. bythincola, sp. nov. Differing from Brada in lacking a tuberculated integument and in being densely and uniformly clothed with long, fine filaments. The neuropodial setae are relatively much larger and are not suggestive of the crochet-type. Ilyphagus bythincola, sp. nov.^ Plate 69, fig. 4-9. The three type-specimens are deformed by pressure. All are densely clothed with closely adherent mud. The anterior end is retracted, preventing satisfactory exainination of the prostomium and its appendages. The largest specimen is 50 mm. long, and in its present flattened condition measures 25 nam., or half the length, across the middle. The number of somites, while not precisely determinable, is small, not exceeding forty. The entire body is covered with a dense, felt-like coat of slender, hair-hke, uniform, cuticular filaments. The ventral setae are conspicuously coarser than the dorsals. They are yellow, or somewhat straw-colored. In the middle region eight, or about that number, in each fascicle. Each seta narrows con- tinuously and conspicuously distad, being drawn out into a long, fine, straight, or somewhat curved, tip. The seta also narrows toward the base. The annuli ' 'iXiis, mud, and ^ayos, a glutton. - Pvdos, deeps of the sea, and incola, inhabitant. IL^THAGUS ASCENDENS. 403 are short and strongly marked; as usual, they become proportionately longer distad, though the absolute increase is not gi'eat and the relative increase not so great as frequent in species of related genera. (Plate 69, fig. 7-9). The dorsal setae have a similar structure, but are very much finer, with the annuli commonly longer. (Plate 69, fig. 4-6). The specimens give no evidence of the longer special setae such as form a head-cage in most genera. Locality. OfT Mexico: Sta. 3415 (lat. 14° 46' N., long. 98° 40' W.). Depth 1,879 fms. Bottom of green mud and Globigerina ooze. 10 April, 1891. Three specimens. Ilyphagus PLUTO, sp. nov. This is a smaller and notably more slender species than the preceding, subcylindrical, moderately narrowed cephalad, the anterior end a Uttle obUquely truncate, while at the posterior end the body is abruptly narrowed so as to present a short, much narrower, caudal region. Surface covered with filaments as in the preceding species, but these less dense and rather coarser proportionately. Adhering to this coat was much foreign material, including, e.g., shells of Foraminifera. Around the margin of the truncate anterior end, which has a diameter of 8 mm., is a series of twenty stout, cylindrical processes distally divided into short rounded lobes, these being apparently retracted branchiae; the processes are laterally contiguous and form a completely closed circle. Whereas in bythincola the coarse ventral setae are pale straw colored throughout, in the present species they are much darker, reddish brown or sorrel-colored, excepting the extreme tips, which are pale. They are long and stout and terete, excepting at the tips, where they are flattened and moderately curved, with acute apex. In middle region of body, 19 mm. long. Notopodials also red-colored; smaller than the neuropodials, but much coarser in proportion than in bythincola. Setae of anterior region lost. Length, 42 mm.; width, 11.5 mm. Locality. Off Peru: 88 m. S. W. of Palominos Light House. Sta. 4672 (lat. 13° 11' 30" S., long., 78° 18' W.). Depth 2,845 fms. Bottom of fine dark green mud. Bottom temp. 35.1° F. 21 November, 1904. Ilyphagus ascendens, sp. nov. In general appearance much more resembling bythincola than the preceding species. The type is a little longer than those of abyssicola and is more uniform 404 THE ANNELIDA POLYCHAETA. in width, not so noticeably widening toward one end. Rounded at the ends. Body densely clothed with slender filaments forming a thick coat, as in the other species. The neuropodial setae are pale brown, being a little darker than in bythin- cola. Wliereas in the latter species the neuropodial setae are apparently of nearly equal stoutness tliroughout the length of the body, in the present species they become very much more slender caudad, the long anterior ones being very much coarser than the most posterior ones. Most setae in the type are broken off near the base; the longest anterior one, which is distally incomplete, is in the present condition 44 mm. long, so that originally it must have approached the body in length. Notopodials very fine and short, pale. Length, 55 mm.; greatest width, 22 mm. Locality. Galapagos: ofT Hood Island, 12 miles S. E. of Ripple Point. Sta. 4649 (lat. 1° 35' S., long. 89° 30' W.). Depth 633 fms. Bottom of Ught grey Globigerina ooze. Bottom temp. 39.5° F. 10 November, 1904. Stern ASPiDAE. These are highly specialized polychaetes, of very distinctive appearance. The body is short, consisting in superficial appearance of 19-22 somites, but morphologically, as judged by the number of fasciae of setae in the posterior region, composed of thu-ty-one somites (*S. scutata Rietsch, Ann. sci. nat., 1882, 13, p. 7; Vijdevsky, Densk. Akad. wissen. Wien, 1882, 43, p. 35). Of these, fifteen Ue in front of the ventral shield, a chai-acteristic double horny, but not truly chitinous (Goodrich, Quart, journ. micr. sci., 1898, 40, p. 239) plate or shield, from the edges of which radiate fasciae of long setae on the ventral sur- face at the posterior end of the body. The first seven somites in the state of repose are retractile. The integument in general is covered with numerous fine, hair-hke papillae, which are typically more numerous and coarse caudad of the seventh somite. The integument caudad of this somite is commonly also longitudinally fm-rowed, or striate. To the surface adhere numerous, chiefly sUicious, particles, much as in the FlabelUgeridae. The prostomium is a very small rounded lobe just over, or in front of, the mouth. It bears neither eyes nor appendages. Peristomium, or first somite, without setae. The anus opens on a papilla above the ventral shield. On each side of and above the anal papilla are two dense bundles of long. STERXASPIS FOSSOR. 405 filamentous branchiae arising from a plate or shield thi-ough perforations in which they pass. No parapodial processes. Each of somites II, III, and IV with a long row of stout acicular setae, or spines, on each side; the distance between the ends of the lateral series above and below increases from somite II to somite IV. No setae on somites V, VI, and VII. Setae of somites VIII to XV, inclusive, are abortive, ordinarily not emerging through the cuticle. The remaining somites have fasciae of long sunple setae which radiate from the edges of the shield, there being (at least in S. scutata) seventeen pairs of these fasciae. The nepliridia are in the form of a single pair of tubercles provided with small, ciliated, internal funnels and nephrostomes, but without external openings. The gonads are represented by a trilobed sac with two ducts, each of which opens at the tip of a slender genital process at the anterior ventral edge of somite VIII (Goodi-ich, Op. cit., p. 233, pi. 15, fig. 1, etc.). The alimentary canal is conspicuously coiled. The pharynx is a conspicuous bulbous division followed by a slender oesophagus. The stomach is much thicker and dilatable, and is followed by a slender intestine which terminates in an expanded rectum. A remarkably long, two-branched proboscis, which is easily lost, has been described for S. spinosus (Sluiter, Naturk. tijds. Neederl. Indie, 1882, 41) and may be present in Ufe in all. These worms have various structural characters suggesting the Echiuroidea, with which group they have often been connected, e.g., by Carus, Gegenbaiu-, and Huxley. In fact, scutata, the first and best known species, was placed by Ranzani in the genus Thalassema; and when Otto made a new genus for it he sought to recall the supposed resemblance by changing the specific name to thalassemoides. Otto, Meckel, and Cuvier regarded Sternaspis as an echino- derm. The species of Sternaspis, the only genus thus far known, live mostly on muddy bottoms, at depths between 15 and 628 fms. S. major, a new species (p. 406), having been taken at the latter depth. Sternaspis Otto. Nova acta Acad. Caes. Leop. nat. curios., 1821, 10, pt. 2, p. 619. Sternaspis fossor Stimpson. Invertb. Grand Manan, 1853, p. 29, pi. 2, fig. 19; Verrill, Invertb. Vineyard Sound, 1873, p. 507, 606, pi. 14, fig. 74; Levinsen, Ofvers. Nordiske Annulata, 1883, pt. 2, p. 214; M.-uienzelleb, Ann. Naturhist. mus. Wien, 1890, 5, p. 5, pi. 5, fig. 4-4b, 5, oa, 7; Augener, Bull. M. C. Z., 1906, 43, p. 191. 406 THE ANNELIDA POLYCHAETA. Sternaspis affinis Stimpson, Proc. Acad. nat. sci. Philad., 1864, p. 159. Sternaspis assimilis Malmgben, Annulata Polychaeta, 1867, p. 87. Sternaspis islandica Malmgren, Op. cit., 1867, p. 87, pi. 14, fig. 85. f Sternaspis fossor Johnson, Proc. Bost. soc. nat. hist., 1901, 29, p. 418; Moore, Proc. Acad. nat. sci. Philad., 1908, p. 191. Sternaspis costata Marenzeller, Denk. K. acad. wissensch. Math. -nat. klasse, 1879, 41, p. 142, taf. 6, fig. 4. This species, as at present conceived, is widespread in the north Atlantic and Pacific Oceans, at moderate depths. Locality. Gulf of Panama: Sta. 3391 (lat. 7° 33' 40" N., long. 79° 43' 20" W.). Depth 153 fms. Bottom of green mud. Bottom temp. 55.8° F. 9 March, 1891. Ten specimens. Sternaspis maior, sp. nov.^ Plate 78, fig. 10. The type is badly broken, so that only the ventral plate or shield can be satisfactorily studied. This plate, however, presents differences in structure and is so much larger than that of S. fossor Stimpson, occurring off the coast of British Columbia and Alaska and than the very closely related S. scutata (Ran- zani) , occurring off Alaska and Japan, as well as in the Atlantic and Mediterra- nean, that it seems obviously a distinct species. The plate is 15 mm. wide, with a length along the median suture of 7 mm. and toward the ends of about 7.75 mm., the ratio of width to average length being two to one. The plate is heavier and the sculpturing obviously coarser than in S. scutata or