PACIFIC TUNICATA OF U.S. NATIONAL MUSEUM 85 



on rectiiiri at level of middle of stomach (fig. 27^). One testicular 

 follicle, proximal portion of vas deferens coils 5-7 times. 



Embryos comparatively large, 1220/* in length in a measured speci- 

 men. Four pairs of ampullae present (fig. 27A), rarely one more 

 excess ampulla may be seen. Larval test frothy. 



Remarks. — The existence of fine crystalline needles in place of 

 spicules, rather heavily pigmented test in most specimens, and rather 

 massive appearance of the colony are the characteristics common to 

 all of the specimens from the Pacific Islands, the colony from Florida, 

 and the type specimen of Dldemnopsis jolense Van Name from the 

 Philippine Islands. These characteristics are considered to be enough 

 to differentiate the present group of specimens from the typical 

 Trldidemnwn savignil (Herdman) which is usually encrusted, con- 

 tains calcareous spicules in the test, and is colored more lightly in 

 preserved state than specimens of the present variety. On the other 

 hand, it is very difficult to regard these characteristics as significant 

 ones to distinguish the present form as a distinct species, because it is 

 well known that the amount of spicules and pigment cells vary con- 

 siderably in T. savlgnii. At present, however, there are no inter- 

 mediate forms in the present material which combine these speci- 

 mens with the typical T. savignih and thus I wish to treat the present 

 specimens provisionally as a variety of T, savignil and retain the name 

 given by Van Name to tlie specimen from Jolo Island of the Philip- 

 pine Islands for the present variety. This variety seems to be dis- 

 tributed widely in the tropical Pacific and also in the West Indies. 



32. TritUdemnum cyclops Michaelseii 



Figure 28 



Trididemnum cyclops Michaelsen, 1921, p. 19, pi. 1, fig. 10. — Hastings, 1931, 



p. 89, fig. 11; pi. 2, fig. B. 

 ? Trididemnum planum Sluiter, 1909, p. 42, pi. 3, fig. 12 ; pi. 7, fig. 7. 



MATERIAL EXAMINED 



Gilbert Islands: Onotoa Atoll; P. E. Cloud, sta. GOC-41. Two colonies 

 (USNM 11482).— A. H. Banner, sta. B-8. Seventeen colonies (USNM 11483). 



Descrii^'iton. — Nineteen colonies from the Gilbert Islands were 

 examined, the largest is 14 mm. X 12 mm. in extent and 2-4 mm. in 

 thickness. They are massive and ovoid in shape, the surface is even 

 and quite free from foreign matter (specimens from B-8) or carries 

 fine snowy white sand grains (specimens from GOC-41). Color 

 of colonies differs according to the amount and the distribution of 

 spicules; specimens from GOC-41 are whitish at places encrusted 

 with fine sand grains and faintly brownish at other portions which 

 are rather sparsely impregnated with spicules so that reddish brown 

 zooids are seen through it, while the specimens from B-8 are slightly 

 grayish white as a whole, being tinted somewhat darker above respec- 



