ASCIDIANS OF THE PHILIPPINES — VAN NAME. 73 



transverse vessels of the first or second order. The infundibula 

 mostly divide near the summit into an anterior and a posterior apex, 

 separated (when the division is sufficiently well marked) by a third 

 order transverse vessel. Stigmata in most places merely short longi- 

 tudinally placed slits arranged as usual in the family Tethyiidae, 

 but as the upper part of an infundibulum is approached they become 

 curved, assuming a spiral arrangement on the apex. Internal longi- 

 tudinal vessels numerous (over 20 on a fold in large individuals), 

 separated on the lower part of the folds by from three to five stig- 

 mata but by six or eight on the intervals between folds. Assuming 

 that two internal longitudinal vessels are to be regarded as belonging 

 to each interval between folds, their distribution in a medium-sized 

 specimen was about as follows: 



dorsal 1 (15) 2 (17) 2 (19) 2 (18) 2 (15) 2 (12) 2 (10) 2 ventral. 



Digestive tract forming a broad, open loop; stomach elongated, 

 not well differentiated from the other parts of the tract except by 

 bearing on its dorsal surface numerous short crooked branching 

 hepatic tubules of a green color. Rectum short, margin of anus thin 

 and irregular but not deeply lobed. 



No kidney was found. 



A gonad is present on the right side only. It consists of a long 

 curved obliquely placed oviduct (probably accompanied by a sperm 

 duct) ending close to the base of the atrial tube and bearing along 

 each side small pear-shaped or irregularly rounded sacs (a dozen or 

 20 in all) connected with it by short side ducts. Each sac contains 

 eggs in the proximal part and a number of small testes of oval form 

 in the distal part. 



Collected only at station D5536 (between Negros and Siquijor, 

 279 fathoms, green mud ; Aug. 19, 1909). Over a dozen specimens 

 (No. 140; Cat. No. 6036 type and 6035 paratypes, U.S.N.M.). 



Genus PYURA Molina, 1810. 



[Cynthia s. Halocynthia Authors, part.] 



In the present paper the writer adopts Huntsman's (1912) limita- 

 tion of the genus Tethyum to T. papillosum (Linnaeus) and its near 

 allies having a number of small bottle-shaped gonads (often more or 

 less fused together by their closed ends) on each side of the body, 

 leaving the name Pyura Molina still available for the majority of 

 the members of the old genus Cynthia Savigny, 1816. These have the 

 dorsal lamina replaced by a series of languets, the intestine forming 

 a widely open loop, and one or two elongate gonads (sometimes con- 

 sisting of small separate glands arranged along a common duct) on 

 each side of the body. 



