394 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



parison seemed justified, but having learned how 

 unreliable are such striking characters as the huge 

 tack-like tables in the skin, I feel that the Yucatan 

 species must be withdrawn as a possibly slightly 

 older stage of Selenka's princeps, one in which the 

 large, tack-like spicules have completely dis- 

 appeared. 



12 Holothuria cubana Ludwig 



FIO. 66: 24-28 



Holothuria cubana Ludwig, 1875, p. 104, pi. 7, fig. 34; 

 Deichmann, 1930, p. 54, pi. 1, figs. 1-8. 



Diagnosis. — Up to 15 cm. long, flattened with 

 blunt ends, ventral mouth with 20 small tentacles. 

 Tube feet ventrally small and scattered, often re- 

 tracted into pits, dorsally few and papilliform. 

 Color white or gray. Spicules a crowded layer 

 of tables with knobbed disk and spire gradually 

 transformed into a reticulated hemisphere. Inner 

 layer of knobbed buttons, short, strongly knobbed 

 with three pairs of holes on the dorsal side; ven- 

 trally mostly larger with four to six pairs of holes 

 and less strongly knobbed, sometimes almost 



smooth. Type: Vienna. Type locality: OS Cuba. 

 Distribution: Reported from the West Indies 

 from Florida, Curagao, Barbados, and Bermuda. 

 This burrowing form should find excellent con- 

 ditions in the sandy flats in the Gulf of Mexico. 



13 Holothuria pseudofossor Deichmann 



FIG. 66: 29-30 



Holothuria pseudofossor Deichmann, 1930, p. 57, pi. 1 

 figs. 9-14. 



Diagnosis. — Resembles H. cubana but has larger 

 appendages and these are more inclined to remain 

 expanded. The spicules are regular tables with 

 eight marginal holes, more or less knobbed edge 

 and low spire with numerous teeth. The buttons 

 have three to seven pairs of holes and large and 

 small ones are found intermingled; the surface is 

 knobbed to smooth. Type: Museum of Com- 

 parative Zoology. Type locality: Montego Bay, 

 Jamaica. Distribution: So far known only from 

 the type locality where it is fairly common, buried 

 in sand under slabs of coral rocks. 



Order 3 DENDROCHIROTA Grube 



KEY TO THE FAMILIES KNOWN FROM THE GULF OF MEXICO 



1. Part of the ventral side developed as a sole, while the remaining part of the body is covered by scales. _2. Psolidae, p. 401 



1. Part of the ventral side not set off as a sole 2 



2. Tentacles 10, often the 2 ventral smaller. (In some deep water forms the number reduced to 8, and the tentacles 



almost unbranched.) 1. Cucumariidae, p. 394 



2. Tentacles 20, in 2 more or less distinct circles 3. Phyllophoridae, p. 402 



1 Cucumariidae 



KEY TO THE GENERA KNOWN FROM THE GULF OF MEXICO 



1 . Shallow water forms 2 



1. Deep water forms (at least around 100 fathoms depth). Body covered by large circular scales 8 



2. Calcareous ring tubular, with distinct tails 3 



2. Calcareous ring simple, or with short posterior prolongation 6 



3. Spicules predominantly elongate plates with a varying number of holes, usually in two rows. Feet scattered over the 



entire surface in the adult animals 4. Thyoneria nom. nov., p. 398 



3. Spicules not predominantly elongate plates 4 



4. Spicules four-holed buttons, forming a crowded layer in the skin 3. Neothyone Deichmann, p. 397 



4. Spicules tables with four to eight holes in disk and two to four-pillared spire; spicules in some forms reduced with age.. 5 



5. Tube feet in five crowded bands 1. Pentamera Ayres, p. 395 



5. Tube feet scattered over entire surface of body, except in very young individuals 2. Thyone Oken s. str., p. 395 



6. Dorsal side with large waits; ventral tube feet in three broad bands; short, box-like form, chocolate brown 



7. Pentacta Goldfuss, p. 399 



6. Dorsal side not with large warts 7 



7. Ring low, simple. Spicules regularly knobbed buttons and an outer layer of deep baskets with a wreath of short 



spines along the rim. Stout, barrel-shaped or lemon-shaped form with thick skin, large oral valves and tube feet 

 scattered over the body 6. Euthyonacla nom. nov., p. 399 



7. Ring simple or with short posterior prolongations. Spicules mostly knobbed button?, irregular or regular. 



5. Thyonella Verrill, p. 399 



8. Plates with excentric spire 8. Echinociicumis Sars, p. 400 



8. Plates with centrally placed spire or spine 9. Sphaerothuria hndwig, p. iOO 



