PACIFIC TUNICATA OF U.S. NATIONAL MUSEUM 131 



different] y ; middle intestine pinkish, while proximal part, of the rectum 

 somewhat yellowish. Anus bilobed, opens at posterodorsal corner of 

 thorax. A triangular or rouglily quadrate whitish and opaque tissue 

 of moderate size, probably the circumintestinal gland, found in intes- 

 tinal loop by rectum at level x^osterior to pyloric end of the stomach. 

 Testicular follices 13-16; ovary located posterior to middle of 

 postabdomen. 



Larvae very large, up to 1.4 mm. in length. Three attachment 

 processes disc-shaped and arranged in a triangle, their basal portions 

 remarkably swollen. Alimentary organ situated on ventral side of 

 trunk nearly at middle. Two pigment flecks of sensory organ 

 arranged dorsoventrally. These structures confonn well to those 

 described previously (Tokioka, 1955) on specimens from the Palau 

 Islands. 



Remarks. — The present colonies differ remarkably from those 

 described by Sluiter (1909) or Tokioka (1955) in that they are all 

 provided with peduncular portion. Sluiter's original specimen is a 

 large 40 mm. X 60 mm. spongelike mass, varying in thickness from 

 5 mm. to 8 mm., and Tokioka's specimens are much smaller, being 

 less than 20 mm. X 40 mm. in extent; they are all devoid of the 

 peduncular portion, except a small 13 mm. long colony from the Palau 

 Islands, which has a peduncle-like portion as shown in Tokioka's 

 paper (pi. 5, fig. 15). As the structures of zooids in the present 

 colonies are exactly the same as those previously described on the 

 Palau specimens, I am inclined to consider the present colonies identi- 

 cal with D. TTiikropnoa. Very probably the pedunculate appearance 

 of the present specimens may be attributable to a special environmental 

 condition, perhaps they might have grown in some narrow spaces, 

 such as crevices or among coral fragments. 



58. Distaplia cylindrica (Lesson) forma typica 



Figure 47 



Holozoa cylindrica Lesson, 1830, p. 439. 



Eolozoa cylindrica f. typica Arnback-Christie-Linde, 1950, p. 33, figs. 9-10; 

 pi. G, figs. 29-30. 



MATERIAL EXAMINED 



Antarctica : Off Knox Coast ; caught at surface of ocean, nos. 106 and 107. 

 U.S. Navy Antarctic Expedition, coll. Mr. Layton, January 19, 1948. Three 

 colonies (USNM 11786). 



Description. — Three ropelike colonies are in the collection, 134 cm., 

 115 cm., and 57 cm. in length, while the width never reaches beyond 

 30-40 mm. Colonies are all rather flattened and seem to be in an 

 imperfect condition, as one or both ends of respective colonies are 

 torn considerably. In the first colony the proximal part about 20 cm. 



