16 ART. 8. 1. IKEDA : THREE NEW AND 



ends. Proboscis six times as long as the body ; slender. Color 

 grayish brown with minute blackish brown flecks. Ventral 

 hooks numerous. Anal gland branched, bearing numerous stalked 

 funnels. 



The male. Found in body-cavity of female. Unusually large, 

 being nearly 30 mm. long ; without ventral hook. The greater 

 part of the thickness of the body-wall presents a trabecular 

 structure. Alimentary canal broken up into numerous vesicles. 

 No nerve-ring is found. Testis in the same position and of 

 essentially similar structure, as the ovary of female. Vas deferens 

 divides posteriorly into four branches, each ending with a ciliated 

 funnel. 



2. Thalasseina tœnloides I. Ike da. 



Fig. 3, PI. T. ; figs. 18-22, PI. IL ; figs. 23-36, PI. III. ; 

 figs. 37-47, PI. IV. 



1904. Th. Umioides, I. Ikeda, Jour. Sei. Coll., Vol. XX., Art. 4, p. 63. 



First an account of the circumstances that led to the dis- 

 covery of the species may be given. 



For a number of past years, the proboscis alone of the worm 

 had been a rather well-known object to Japanese collectors, though 

 its real nature had remained a standing puzzle to them. They 

 had to do with a long, flat, bandlike object that often reached a 

 length of one meter or more and had a breadth of 1-1 s cm. It 

 was somewhat convex on one side and slightly concave on. the 

 other, the latter showing further a median longitudinal groove. 

 Both sides presented a bluish-gray ground-color, variegated with 



