552 PBOCEEDINGS OF THE NATIONAL MUSEUM. 



one, behind whicli there are four additional obscurely biannulate pre- 

 anal annuli. 



There are eleven pairs of well-developed lateral vesicles, which 

 diminish in size each way from the sixth. Behind the eleventh pair 

 are two pairs of rudimentary vesicles, indicated by opaque whitish 

 lateral thickenings of the rings. The well-developed vesicles occupy 

 the sides of 6 1 and h 2 of their somites, except the first, which 

 extends onto the last ring of somite XI. There are indications of annu- 

 lation of the anterior sucker, but too obscure in this specimen to be 

 described. 



No. 242, U.S.N.M. Woods Hole, Massachusetts; Y. K Edwards. 

 One specimen. 



g. TRACHELOBDELLA MACULATA, new species. 

 (Plate XL, fig. 6.) 



The two body regions are well marked, the anterior slender and 

 terete, the posterior broad, flattened, and raquet-shaped. The posterior 

 sucker is small, little if at all directed ventral ward, and is contracted 

 to a slit-like opening. 



There are thirteen pairs of respiratory vesicles, with a posterior rudi- 

 mentary fourteenth. The anterior ones are indistinct and the largest 

 (the ninth and tenth pairs) at the widest pjirt of the body. This region 

 is concave below and convex above from side to side. The anterior 

 region is somewhat retracted within the posterior. The head (in the 

 contracted specimen) is scarcely expanded, and its margin only slightly 

 oblique. Its free margin tends to fold into four lobes, dorsal, ventral 

 and two lateral. 



As in most other species of the genus, the annulation of the anterior 

 region is irregular and difficult of interpretation. In this specimen the 

 difficulty is increased owing to the integument being gathered up at 

 several spots, as it were, into loose tufts, which disturb the arrangement 

 of the annuli. After a careful study I have fixed on. the interpretation 

 shown in the figure; but this needs to be confirmed by a study of more 

 and better material. The clitellar region is sufficiently distinct. Six 

 annulations are observable on the dorsal side of the head. Then follow 

 two narrow rings in the constriction behind the head. Behind these 

 follow, apparently, four complete somites (V to VIII) of three rings 

 each, of which the first corresponds closely to the transverse bands of 

 orange, the second and third to the ashy spots described below. The 

 primary rings of somite VIII, as here provisionally identified, are sub- 

 divided into six secondary rings. The clitellum consists of the two 

 primary partly orange colored rings of somite IX, the two primary 

 (divided into four secondary) uncolored rings of somite X, and the 

 similarly constituted somite XI, of which the last ring is united with 

 the first of somite XII. The male pore is between the two secondary 

 rings of aunulus seventeen (the first of somite X), and the female pore 



