84 UNITED STATES NATIONAL AIUSEUM BULLETIN 251 



of colony nearly smooth, although depressed irregularly at some 

 places where a number of minute whitish granules are seen in some 

 specimens. Some colonies may carry fine sand grains on surface. 

 Lacunae in some colonies sometimes full of eggs of a parasitic har- 

 pacticoid copepod. 



A large colony from Florida was carried on the back of a Dromid 

 crab (USNM 11770, 33 mm. in carapace length), 80 mm. X 50 mm. in 

 extent, 40 mm. in height and irregularly lobate as shown in figure 27«. 

 Test somewhat hard, gelatinous, translucent, and grayish yellow, sur- 

 face smooth and quite free from any foreign matter, sprinkled with 

 small dark irregiilarly shaped spots, 1-4 mm. long. Colony reaches 

 25 mm. in thickness at some places, where hypoabdominal lacunae are 

 well developed and bottom layer is remarkably thickened; zooidal 

 stratum only 2 mm. in thickness. Crystalline needles found in test, 

 but no perfect spicules; no system defined in zooid arrangement. 

 This specimen differs remarkablj^ from Pacific specimens in its larger 

 size and lighter coloration of the colony, but can most safely be treated 

 as a giant form of the present variety. 



The type specimen of Diderrwiopsis jolense Van Name (USNM 

 6040), 23 mm. X 10 mm. in extent and 4 mm. in thickness, was col- 

 lected during the Alhatross Philippine Expedition, 1907-09, at sta. 

 5137 in the vicinity of Jolo, 20 fathoms, on Feb. 14, 1908. Test soft, 

 gelatinous, translucent, and pale brownisli ; no zoochlorellae or per- 

 fect spicules included. Test somewhat frothy in consistency ; bladder 

 cells abundant, oval in shape and 55-70/x, in long diameter; granular 

 cells also oval in outline, 35^0/x in long diameter and containing 10-15 

 granules in each, while spherical cells are usually less than 25ju, in 

 diameter and with homogeneous contents. Pigment cells may reach 

 120/A in longer ones and crystalline needles found sparsely in test are 

 very small, only 13-18/i, in length. 



Zooids comparatively large; thorax is 630/x in a contracted state in 

 a specimen examined, abdomen 1 to ly^ times as long as contracted 

 thorax, attaining 1000-1110/a in specimens examined. Zooids pig- 

 mented in dark purplish brown or dark green, especially heavily on 

 thoracic mantle and along both sides of endostyle. Only zooids of 

 the specimen from the Palau Islands (USNM 11438) are lightly pig- 

 mented and tinted salmon pink. Branchial aperture 6-lobed; atrial 

 siphon short but distinct, lobation around the aperture may be indis- 

 tinct in some specimens, but rather clearly defined in six (?) lobules 

 in others. Retractile muscle up to I14 times as long as contracted 

 thorax. About 8 stigmata in each of throe roAVs; many yellowish 

 corpuscles aggregafed in wall of branchial sac between stigmata. 

 Tentacles about a dozen ( ? ) , Abdomen placed nearly vertically and 

 intestine not curved so strongly as in Dideninvm, {Dldemmnn). Cat- 

 cumintestinal ixland consists of about 8 longitudinal tubules running 



