ASCIDIANS OF THE PHILIPPINES VAN NAME. 109 



20 to 30 in total number in large zooids, are distributed in the two 

 rows, one on each side of the mid-ventral line. The row on the 

 right side is the longest, not only extending nearly to the posterior 

 end of the body, but at that point curving dorsally and extending 

 a little way forward in the dorsal region of the right side. The row 

 on the left side does not, ordinarily at least, reach near to the poste- 

 rior end of the body. The testes are not grouped into distant 

 gonads; they are small rounded or pear-shaped glands, not cleft 

 into lobes, and are very numerous, being distributed in groups, irreg- 

 ular rows, or singly on the inner surface of the mantle. They are 

 most abundant on the posterior dorsal region, chiefly but not entirely 

 to the right of the mid-dorsal line. They are also very abundant in 

 the ventral region, among or alongside of the female gonads. A 

 few are scattered in other places, especially on the right side of the 

 body, and in continuation forward or backward of the rows of 

 female gonads. The sperm ducts are difficult to trace, but it is evi- 

 dent that those of testes lying near together in a group often join 

 to form common ducts. 

 The specimens are from the following localities : 



No. 130. Station 5134 (off Balukbaluk Island. Sulu Archipelago, 25 

 fathoms, fine sand, Feb. 7, 190S). Large colony; no repro- 

 ductive organs found In zooids. (Cat. No. 5995, U.S.N.M.). 



No. 113. Station D5136 (near Jolo Light, 20 fathoms, sand and shells, 

 Feb. 14, 1908). Large colony; no reproductive organs found 

 in zooids. (Cat. No. 5994, U.S.N.M.). 



No. 121. Station D5174 (off Jolo Light, 29 fathoms, coarse sand. Mar. 5, 

 190S). Type colony. (Cat. No. 6042, U.S.N.M.) 



No. 17. Station D5555 (off Capalian Point. Jolo, 34 fathoms, coarse sand, 

 Sept. 18, 1909). (Cat. No. 5996, U.S.N.M.). 



In the distribution of the gonads this species differs somewhat 

 from those thus far included in the genus Stolonica. It might be 

 placed in the genus Heterocarpa Lacaze-Duthiers and Dalage (1892) 

 as modified and defined by Michaelsen (1911) with but little altera- 

 tion of his diagnosis except that the existence of budding and the 

 formation of true colonies is uncertain in the species thus far placed 

 in Heterocarpa. The writer can not feel any doubt of it in the case 

 of the present species; moreover if compound species are admitted 

 to Heterocarpa the chief reason for maintaining it as a distinct genus 

 disappears. 



STOLONICA VESICULARIS, new species. 



Plate 32, fig. 39. 



The colony or colonies in the only specimen almost entirely cover 

 the surface of the body of a large simple ascidian (Microcosmus 

 exasperatus Heller). The zooids are rounded and sac-like, some- 

 times higher than wide, and attached by the posterior end, but only 



