GULF OF MEXICO 



405 



Genus 5 PIIYLLOPHORUS Grube, 1840 

 Phyllophorus dobsoni Bell 



Phyltophorus dobsoni Bell, 1883, p. 60, pi. 5, figs. 5, 5a- 

 b; Deichmann, 1930, p. 141. 



Diagnosis. — Type 8 cm. long, barrel-shaped, 

 with conical feet scattered over the entire body. 

 Color brownish. Calcareous ring short, tubular 

 with short posterior tails. Spicules small disks, 

 with four or more small holes and a few scattered 

 knobs. Type: British Museum. Type locality: 

 Bay of Honduras. So far no other specimens 

 have ever been recorded, but one would naturally 

 expect that the species would also occur in the 

 Gulf of Mexico. 



How the spicules are in young individuals is 

 unknown, and the only other phyllophorid with 

 similar spicules is Sluiter's P. transvectus from the 

 East Indies known from the type and one other 

 specimen. The similarity between the two species 

 is so great that one wonders whether there possibly 

 may be a mistake in the geographic location. 

 Thus Domantay (1933) mentions a "Honduras 

 Bay" in the Philippines, so there is the possibility 

 that Bell's species might have come from that 

 locality and not Central America. 



Genus 6 BENTHOPHYLLOPHORUS nom. nov. 



New name for Thyonidium conchilegum Pourtal^s. 



Benthophyllophorus conchilegum (Pourtalds), 1868 



FIO. 68: 17-20 



Thyonidium conchilegum Pourtalfes, 1868, p. 128; 1869, 

 pp. 359, 361. 



Phyllophorus conchilegum Deichmann, 1930, p. 142, pi. 

 17, figs. 14-15. 



Diagnosis. — Small form, 4 to 5 cm. long, with 

 20 tentacles of unequal size in 2 indistinct circles. 

 Feet few large, scattered. Skin stiff, rough from 

 spicules. Color in alcohol whitish. Spicules ta- 

 bles with circular disk with about eight marginal 

 holes, four pillars and spire ending in numerous 

 small teeth. Introvert with large tables with 

 irregular disk. Type: Museum of Comparative 

 Zoology. Type locality: Off Sand Key. Distri- 

 bution: Known only from the waters around Flor- 

 ida, from 100 to 189 fathoms depth. Lives un- 

 doubtedly in soft mud, judging from the content 

 of the intestine. It is a typical deep water form 

 with no affinities to any other known phylloph- 

 orid. 



Order 4 MOLPADONIA 



The West Atlantic members of this order were treated by Deichmann, 1940, and no changes have 

 been made since that time. 



KEY TO THE GENERA .\ND SPECIES OF MOLPADONIA KNOWN FROM THE GULF OF MEXICO 



1. Thick-skinned forms with barrel-shaped body which tapers off into a long stout tail. Tentacles 15 with 2 pairs of 

 lateral digits (and no terminal digit). Color dirty white. Spicules numerous, small disk-shaped bodies ("cross- 

 cups"). Few fathoms depth 2. Paracaudina Heding. One species. 



Paracaudina obesacauda (H. L. Clark), p. 406 



1. Thin-skinned forms with barrel-shaped body which quickly contracts to a short thin tail. Tentacles 15 with a terminal 



digit and a few pairs of lateral digits. Spicules derived from tables or developed as huge rods or plates; in some 

 species skin red from phosphatic bodies. 1. Molpadia Cuvier 2 



2. Spicules chiefly one-pillared tables with three to six holes in disk; in older individuals fusiform rods or thromboid plates 



dominate. Usually numerous phosphatic bodies 1. Molpadia musculus (Risso), p. 405 



2. Spicules chiefly three-pillared tables 3 



3. Tables large, with numerous holes; phosphatic bodies seem to be totally lacking.. 2. Molpadia barbouri Deichmann, p. 406 

 3. Phosphatic bodies present in varying amount. Tables small with three to six holes in disk; numerous holes in disk 



of tables in tail 3. Molpadia cubana Deichmann, p. 406 



Genus 1 MOLPADIA Cuvier, 1817 Spicules one-pillarcd tables with three to six holes 



1 Molpadia musculus (Risso) often one to three marginal projections. In older 



See Clark, 1907, p. 165, pi. 23, figs. 4-7 (complete list individuals these spicules are superseded by huge 



of references); also Deichmann 1940, p. 225, pi. 40, figs. fusiform rods or rhomboid plates. TaU with fusi- 



'"^5- form rods, with or without a small spire. Type: 



Diagnosis. — Large species up to 16 cm. long Lost. Type locality: Mediterranean Sea, un- 



with varying amounts of phosphatic bodies. doubtedly from less than 200 fathoms. Distribu- 



