386 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



existing. Type locality: Coast of Norway. 

 Distribution: From Murman coast, Norway to the 

 Azores; also in the Mediterranean; in the western 

 Atlantic taken off the Lesser Antilles and off 

 Florida {Fish Hawk), 200 fathoms. According to 

 Mortensen (1927), from 10 to 1,000 fathoms. 

 The extreme low depth may refer to the most 

 northern localities; usually the species lives at 200 

 fathoms or more. As far as the present records go 

 the species is not common in the American waters, 

 but it msLj very likely occm- in numbers on the 

 extensive areas of muddy bottom in the Gulf of 

 Mexico. 



4 Mesothuria gargantua Detchmann 



Holoihuria verrilli TMel (partim), 1886b, p. 6. 

 Mesothuria gargantua Deichmann, 1930, p. 95, pi. 7, 

 fig. 1; 1940, p. 191. 



Diagnosis. — Large robust form, 20 cm. long, 

 with stout, cylindrical feet over entire surface 

 except the anterior part of the ventrum; dorsal 

 feet slightly smaller. Spicules tables with irregu- 

 lar disk with numerous holes and four-pillared 

 spire with numerous spines on the top. Feet with 

 vestige of end plate or none; tables as those in 

 the skin. Type: Museum of Comparative Zool- 

 ogy- Type locality: Off Barbados, 394 fathoms. 



Distribution: Off the Lesser Antilles (Blake); 

 north of Cuba (Atlantis). From 394 to 500 

 fathoms. This robust species may possibly be 

 common in deeper water of coasts of Cuba and 

 Yucatan. 



Genus 3 ZYGOTHURIA Perrier, 1898 

 Zygothuria lactea (Theel) 



Holoihuria lactea Th6el, 1886, p. 183. 

 Zygothuria lactea Deichmann, 1930, p. 108, pi. 8, figs. 

 8-9; 1940, p. 190. 



Diagnosis. — Large flattened forms, 15 cm. long, 

 with few tube feet along the margin. Spicules, 

 fragile tables with six large holes in the disk, and 

 slender, thi-ee-pillared spire with either tlu-ee long, 

 diverging spines or a single pointed rod. Type: 

 British Museum. Type locality: Off New Zea- 

 land. Distribution: Widespread in the Pacific and 

 Atlantic Oceans; common along the coast of New 

 England, in the West Indies and also taken in the 

 Gulf of Mexico. From about 350 to 1 ,000 fathoms. 



The Albatross collected it in various localities in 

 the Gulf, while the Atlantis dredged it in San 

 Nicholas Channel, northern Cuba. One would 

 expect it to be one of the most common species 

 in the muddy part of the Gulf. 



Genus 4 BATHYPLOTES Oestergren, 1896 



KEY TO THE SPECIES FOUND IN THE GULF OF MEXICO 



1. Disk of tables often forming a complete circle with a large number of large holes in each of the four sections. Dorsal 

 side flattened; ventral side with small fungiform papillae in two bands 3. Balhyplotes bigelowi Deichmann, p. 387 



1 . Disk of tables cross-formed 2 



2. Arms with few holes, often incomplete; spire snmooth, without teeth. Dorsal side high, vaulted with large papillae; 



ventral side with large fungiform papillae 2. Balhyplotes pourtalesi (Th6el), p. 386 



2. Arms with numerous small holes; spire with teeth along the sides. Dorsal side flattened; no large fungiform papillae 

 on the ventrum (if any are present they are quite small) 1. Balhyplotes nalans (M. Sars), p. 386 



1 Balhyplotes natans (M. Sars) Indies reported from the Gulf of Mexico, 335 and 



Holoihuria natans M. Sars, 1868, p. 4. 337 fathoms depth (Albat.ross Station 2396 and 



Balhyplotes natans Deichmann, 1930, p. 100, pi. 9, figs. 2398). The species is also reported from the 



^~^' ^- Japanese waters (Mortensen, 1927, p. 385), but 



Diagnosis. — Flattened, large form with marginal the latter record needs reinvestigation, 

 row of papillae; dorsal side with few papillae in 



indistinct rows. Ventral side with lateral rows of ' Bathyplotes pourtalesi (Th6el) 



appendages and sometimes some scattered on the Stichopus pourtalesi Th^el, 1886a, p. 4. 



ventral sole but none in the midventral ambula- Balhyplotes pourtalesi, Deichmann, 1930, p. 102, pi. 9, 



crum. Spicules tables with cross-shaped disk with ^^^- '^~''' l'-*"*"' P- ^^^' P'- "^'' ^^^- ^~^- 



a large number of small holes. Type: Not exist- Diagnosis. — Large form, 20 cm. or more, with 



ing. Type locality: Lofoten, Norway. Distribu- high, vaulted dorsal side, thick-skinned with large 



tion: In the eastern Atlantic from Lofoten to Cape papillae (often thrown off m. long strips); ventral 



Verdes, from 100 to 800 fathoms; in the West side with large fungiform papillae. Spicules 



