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BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



gonad, lying .against the side which is attached to the mantle. The 

 individual figured (fig. 41) has 5 gonads on the left and 10 on the 

 right side ; another has about G on the left and 8 on the right side. 



There are two specimens (No. 136) (Cat. No. 6041, U.S.N.M.) of 

 this species from station D5159 (off Tinakta Island, Sulu Archi- 

 pelago, 10 fathoms, coral sand, Feb. 21, 1908), both of nearly the 

 same size and form. The stouter one is the type. There is also, in 

 a bottle with no locality, a broader and more flattened specimen (No! 

 151) (Cat. No. 5991, U.S.N.M.), with an irregular laterally extend- 

 ing pedicel-like process of the test arising from the posterior part of 

 the body, which evidently assisted in attaching the animal. The 

 orifice of the dorsal tubercle is irregularly U-shaped instead of horse- 

 shoe shaped, but, as in the other specimens, the open interval is 



forward. Though the 

 individual has no re- 

 productive organs de- 

 veloped, it is probably 

 of this species, which 

 is apparently most 

 closely allied to Stye- 

 la clara Hartmeyer 

 (1906, p. 13, text-fig. 

 7), from Hakodato, 

 Japan. That form, 

 however, has but four 

 gonads on each side, fewer internal longitudinal vessels, atrial ten- 

 tacles present, and a differently shaped body. 



A small specimen (No. 20) (Cat. No. 5932, U.S.N.M.) from sta- 

 tion D5145 (near Jolo Light, February 15, 1908, 23 fathoms, coral 

 and shells) may also belong to this species, but is so immature that 

 this is uncertain. It has the body about 19 mm. long and is attached 

 obliquely by the posterior end, which is produced into a pedicel-like 

 extension that evidently assisted in attaching the body as in the case 

 of the last-described specimen. The body surface is smoother than in 

 the specimens described, though somewhat wrinkled, and the color 

 is nearly white. In its internal structure it apparently corresponds 

 sufficiently well with the present species if allowance is made for its 

 immature condition. 



Tentacles apparently about 16 in number. 



Dorsal tubercle with a horseshoe-shaped orifice, the open interval 

 forward. 



Dorsal lamina plain-edged. 



Four w T ell-developed branchial folds on each side the internal longi- 

 tudinal vessels distributed about as follows : 



dorsal 3 (14) 5 (12) 4 (13) 4 (9) 4 ventral. 



Figs. 41—43.— Sttela tinaktae, new species. 41, Left 

 and right sides of body. x .75. 42, dorsal tu- 

 BERCLE. X 8. 43, Part of a gonad. (The side occu- 

 pied BY THE TESTES IS ATTACHED TO THE MANTLE.) 



X 12. 



