8 AET. 5. — T. AIDA. 



This species closely resembles Fritillaria sargassi described 

 by LoHMANN, especially in the T-shaped genital glands ; but the 

 following facts have induced me to create it into a distinct species : 

 1 , the presence of deep notches at the base of tail ; 2, the perfectly 

 straight course of œsophagus, not so inclined as in F. sargassi ; 

 and 3, the swelling in a less degree of the lateral lobes of ventral 



lip. 



The largest specimen in my possession measures in trunk 

 909 n and in tail 1490 n long. Greatest breadth of tail 690 p. ; 

 that of its musculature 236 n. 



Genus Oikopleura. 



1. OiTiojileura longicauda Vogt (1854). 

 PI. III., figs. 1-7. 



Buccal gland^^ and Eisen's oikoplast"^ wanting. Blind 

 sac of the left stomach large, finger-shaped and ascend- 

 ing along the posterior wall of oesophagus. Spiracle 

 close to endostyle. Genital gland covers the lateral 

 side of alimentary canal; ovary simple and flat; testis 

 paired. Two hoods, dorsal and ventral, cover the 

 anterior part of trunk. Tail with side musculature 

 and without subchordal cells. 



This species may be easily distinguished by its two hoods, 

 which cover tlie anterior part of the trunk and extend to 

 the mouth, when well developed. The dorsal one of them 



1, 2. About lliese terms see Lohmann's "Das Cieliiuise tier Appeiulioularion, " LS99. 



