38 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



tion are based on studies of three specimens of the solitary form, 

 most generously given by Professor Ritter, the discoverer of the 

 species, and upon three specimens of the aggregated form collected 

 in Philippine waters by the United States Bureau of Fisheries steamer 

 Albatross (station D, 5437, between Bohol and Leyte, north of Min- 

 banao). The specimens given by Professor Ritter came from off the 

 California coast. Two of the three have stolons with well-formed 

 zooids. Specimens of both the solitary and aggregated individuals 

 are in the United States National Museum. 



Cat. No. 6476, U.S.N.M. (solitary form), off San Pedro, California, 

 (W. E. Ritter) ; 3 + specimens. 



Cat. No. 6456, U.S.N.M. (aggregated form), Albatross station D 

 5437, Hermana Mayor Light, west coast of Luzon; May 8, 1909; 

 100-600 fathoms; surface temperature 86° F.; 3+ specimens. 



CYCLOSALPA BAKERI, solitary form. 



Plate 7. 



This is very similar to the solitary Cyclosalpa Jloridana, but there 

 are marked differences. The shape of the body, the test, and the 

 luminous organs in the two are similar, though our specimens of C. 

 balceri show the latter more developed than they are in our specimens 

 of C. Jloridana. All the body muscles are distinct in the solitary C. 

 balceri and none of them are continued across the mid-ventral line. 

 The sixth body muscle on each side, in its dorsal portion, turns for- 

 ward, passing the dorsal ends of the fifth and sixth body muscles. 

 The dorsal oral retractor gives rise, strictly speaking, only to the 

 first or admarginal sphincter of the lower lip. The second sphincter 

 of the upper lip has its fibers inserted upon, but not a part of, the 

 retractor. The first sphincter of the upper lip is continuous directly 

 with the second sphincter of the lower lip, the two forming one con- 

 tinuous muscle. The third sphincter of the lower lip is a branch of 

 the ventral retractor, as in the solitary Cyclosalpa pinnata. The 

 basal three atrial sphincters are well developed and form something 

 of a network, in which one can recognize ventrally the diagonal 

 atrial retractor in its typical position. The delicate atrial sphincters 

 are twice as numerous as in the solitary Cyclosalpa Jloridana. 



For the gut, we need mention only the two caeca, which are of 

 approximately equal size, and are larger than in the solitary form 

 of any other species of Cyclosalpa. 



Figure 20 shows the contour of the aperture of the dorsal tubercle, 

 slightly more curved than in the solitary Cyclosalpa Jloridana. The 

 stolon is straight, lying wholly on the mid-ventral* line, instead of 

 bending to the right as in our specimens of the solitary C. Jloridana. 



