144 ^^^ 



without branches. It is much shorter than in JV. peronea and is sepa- 

 rated from the brain by several times its length, while in N. peronea 

 it is described by Burger {loc. cit.^ p. 549) as reaching nearly to the 

 brain. In one series of sections of N. gracilis the caecum itself ex- 

 tended through seventeen sections only, while there were about seventy- 

 five sections between its anterior end and the brain. 



Nervous Systetn and Sense Organs. — Brain and nervous system 

 present no important deviations from those of N. feronea. Cerebral 

 sense organs small, much elongated, situated far in front of brain and 

 connected with exterior as usual. 



The sexual products ripen late in summer. The ovaries and sperm- 

 aries lie directly above the lateral nerve cords, but when fully devel- 

 oped extend also internal to them. 



Habitat. — Pacific Grove, Calif., among mussels and other growths 

 on rocks at low water. Not common. Collected in same locality in 

 1899 by C. B. Wilson. 



Paranemertes Coe 

 Proc. Wash. Acad. Sci., iii, p. 32, 1901. 



Three species (/*. carnea^ P. peregrzna., P. pallida^ of this genus 

 have been described from Alaska {^loc. clt.).^ A fourth species was 

 found abundantly at San Pedro and San Diego, California. This form 

 agrees with those previously described in general anatomical features, 

 but differs in regard to the number and arrangement of the ocelli, so 

 that the part of the generic diagnosis which refers to the ocelli (p. 32) 

 will have to be amended to read, " Ocelli minute, usually numerous, 

 but sometimes consisting of but a single pair." 



5. PARANEMERTES CALIFORNICA sp. nov. 

 p1. XV, fig. 2 ; pi. xvni, figs. 1-5 ; p1. xxi, figs. 1-9. 

 Body long, moderately slender, rounded or cylindrical in the short 

 esophageal region, very much flattened farther back. Intestinal region 

 much wrinkled when contracted, but smooth when body is well ex- 

 tended. Head small and acutely pointed in ordinary states of contrac- 

 tion. The snout, with the ocelli, can be retracted to a very consider- 

 able extent into the tissues of the head, very much as in some species 

 of TcBniosoma. Intestinal region flat and ribbon-like with thin mar- 

 gins which are sometimes bent towards the ventral surface. Posterior 

 extremity rounded. 



1 Also previous article, identically paged. The peculiar fluted or braided ap- 

 pearance of the stjlets (both central and accessory) of P. peregrina was not 

 described in the previous article but is represented on p1. xx, figs. 14, 15. 



