ASCIDIANS OF THE PHILIPPINES VAN NAME. 



143 



the sides of the colony, but with less obvious regularity on the top. 

 The common cloacal ducts run vertically between every second row 

 of zooids and probably all converge to one common cloacal aperture 

 on the top of the colony. 



Zooids small (not usually over 1.25 mm. long in the preserved 

 state) ; the largest and oldest are in the upper part of the colony. 

 Branchial aperture small, often only slightly prominent; unlobed. 

 Atrial aperture a large opening whose anterior border may be pro- 

 duced into a short languet. 



Mantle thin and transparent. Its musculature is only slightly 

 developed and is mostly confined to the thorax, being composed 

 chiefly of very delicate bands having a transverse or oblique direc- 

 tion or encircling the apertures, but these bands are few and very 

 slender. 



Only eight tentacles of two sizes, placed alter- 

 nately, could be demonstrated with certainty. 



Dorsal languets rather small, arising from the 

 transverse vessels a little to 

 the left of the median dorsal 

 vessel. Branchial sac large, 

 with four rows of stigmata. 

 The rows are arranged in 

 pairs, the first and second sepa- 

 rated only by a narrow trans- 

 verse vessel, and the third and 

 fourth rows also, while be- 

 tween the second and third 



rows a wider vessel intervenes. There are 14 or 15 stigmata in a 

 row on each side in the two anterior rows and one or two less in the 

 posterior ones. 



Intestinal loop small; generally not twisted. Stomach small, pear 

 shaped, tapering toward the pyloric end, and smooth walled. Margin 

 of anus slightly two lipped. 



Only female reproductive organs were found, though many zooids 

 were examined, and these were not greatly developed. They con- 

 sist of a saclike ovary containing a few eggs lying in the dorsal 

 region of the abdomen close against the ascending part of the intes- 

 tinal loop. The largest eggs are in the posterior part of the ovary; 

 the anterior end of the latter appears to be continuous with an ovi- 

 duct accompanying the intestine. No incubatory pouch was found, 

 but its absence may have been due to immaturity of the colony as a 

 whole and of the individual zooids. 



The only specimen (No. 25) (Cat. No. 5926, U.S.N.M.) is from 

 station D5149 (off Sirun Island, Sulu Archipelago, Feb. 18, 1908, 



Figs. 94, 95. — Stcozoa pdlchra (Hkrdman). 

 94, Colony. X .75. 95, Zooid. X 30. 



