280 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 



antero-lateral margin of bead. These are usually arranged in a 

 single elongated and very in-egular cluster on each side. 



Proboscis. — Proboscis sbeatb extends to end of body. Probos- 

 cis of moderate proportions, with remarkably slender basis of central 

 stylet. Few other species of the genus possess so slender a stylet 

 basis, which is four or five times as long as its diameter (PI. 22, fig. 

 161). Basis is of about the same diameter throughout, and is no 

 wider at its posterior end than anteriorly. It measures about 0.1 

 mm. in length and .024 mm. in diameter. Comparative length of 

 central stylet is not known, as the specimens first came into my 

 hands after having been preserved for a few days in formalin, by 

 which the stylet had been partially dissolved. 



Liternal anatomy. — Characterized by an unusual thickness of 

 the basement membrane and a correspondingly large amount of 

 parenchyma separatitig the organs of the body. In this parenchyma 

 the nephridial tubules appear as very distinct, branching canals. In 

 the head the muscular fibers and other tissues are well separated by 

 this same parenchyma. 



Intestinal caeca much reduced, extending forward but a very 

 short distance. 



Cerebral sense organs remarkably small, not much larger in sec- 

 tion than one of the larger ocelli; situated far in front of brain. 



In the single specimen available for sectioning, the brain region 

 was contracted to such an extent that the brain itself was drawn 

 backward beyond the anterior portion of the lateral nerves, so that 

 both brain and lateral nerves appeared in the same section. 



Ilahitat. — Dredged in about 50 fms. off Pott's Valley, Santa 

 Catalina Island, California. Not common. 



The single irregular cluster of ocelli on each side of head and the 

 slenderness of the stylet basis will serve to distinguish this from any 

 of the other described species of the genus from this region. 



71. Amphiporus fulvus, sp. nov. 



PI. 2, fig. 23. 



Body decidedly slender, rounded, of small size; length 15 to 25 

 mm. or more, width rather less than 1 mm. Head slender; lateral 

 oblique grooves as in related species. 



