306 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 



branchs (Venus, Mya, Pholas, Mactra, Cypkina, Cardium, and 

 others). 



86. Malacobdella sp. ? 



Mr. J. F. Abbott informs me that a representative of this genus 

 occurs at Pacific Grove, California. It was found by him on one 

 occasion only, and the specimens were lost before their specific char- 

 acters were determined. 



In addition to the species identified and described above, the col- 

 lections from the U. S. National Museum contain a number of speci- 

 mens which are insufticiently differentiated either in their external 

 appearance or in their internal anatomical peculiarities to warrant 

 any attempt at their classification or description. These unidentified 

 specimens include principally species of Cerebratulus and Amphi- 



PORUS. 



Addendum. 



Since the foregoing pages were put in type, I have been informed 

 by Pi-ofessor Harold Heath of Stanford University of the recent dis- 

 covery of a species of Nectonemertes Verrill in Monterey Bay, 

 California. This remarkable genus has previously been known only 

 from a few individuals of a single species (JV. niirahilis Verrill) col- 

 lected in the North Atlantic Ocean. 



Nectonemertes Verrill. 



Trans. Conn. Acad. Sci., 8, p. 447, PI. 38, fig. 1, 1892. 



Body broad and decidedly flattened, with thin lateral margins 

 head broad ; neck constricted, Avitli pair of cirriform lateral append- 

 ages ; posterior extremity produced into a broad, finlike appendage. 

 Mouth and proboscis aperture separate; intestine straight, with 

 lobed lateral diverticula ; anus at end of caudal " fin." Musculature, 

 blood vascular system, and position of lateral nerves much as in 

 typical Hoplonemertea. Proboscis sheath extends nearly to poste- 

 rior end of body; proboscis without stylets. Ocelli wanting. A 

 cluster of peculiar organs, the nature of which is as yet undeter- 



