1905.] NATURAL SCIENCES OF PHILADELPHIA. 379 



XI 



^5; f;^^.^|;7P^™f^h^^^ open close together in a common depression 

 just behind furrow — . 



n,!^]" ^Tf ""'^ ™""' ^'■°'" P'"'''''' " y°™S ^°™^ to brown or 



of tt ;!!i fTT," °?'''. V° ""^''^ *"" ''°'°'' '^ ''»«= to a combination 

 of tlie rose of the blood witli the brown of the chlorogogue ceUs the 



opaque wh,te of the cclomic corpuscle., the dark content, of the i;tt! 

 tme and the pigment of the slcin. Anteriorly the color remains pink 

 whi e 4 'accumulation of ccelomic corpuscles, becomes opaque 

 white, men, as m certam individuals, the latter are very numerous 

 they impart a characteristic whiteness and opacity to the entire worm' 

 The seta are all of the usual short, bifid, hooked form (fig. 4) with a 

 deeply cleft tip and the terminal process somewhat longef ank more 



« t:"th b", ''" n •"^'°* '^"' °"^- ^'^« Potion of the se a 

 external to the body wall is peculiarly thickened, but otherwise pre- 

 sents no characteristic features. In each bundle the inner seta, are 

 somewhat the longer and those of ventral bundles slightly exceS the 

 dorsal, Ix,t no marked differences are anywhere noticeable "^ usual 

 the ventral bundles of XI are wanting. From II to XI 4 or 5 k the 

 prevalent number in each bundle, the last being most usual in the 



tellum 3 IS usual in the ventral, 2 in dorsal bundles, and both may 

 become reduced to one toward the posterior end 



Owing to the opacity of the body walls and the profusion of ccelomic 

 corpuscles m mature worms the internal anatomy is difficult to work 

 out upon living subjects, though practically all of the results of the 



012^ f °*''"""= '"'T""'^'''^ ('^S- 5) "■■'' from .009 mm. to 



.012.5 mm. in diameter, and filled with a comparatively small number o^ 

 spherical granules measuring .0025 in diameter, and ,vl„se opacitv and 

 whiteness gives to the corpuscles their characteristic aspect' Among 

 these corpuscles are seen a few filled with very much smaller granute 

 which appear to be budded from the high peritoneal cells 



No unusual features are presented by the ahmentary canal The 

 pharyngeal region IS very small, though its glands extend diffusely to 



u' K J'T ' "*^*"" *= '■'^"'''''y ™d prominently sacculated 

 eapecially behind the intestine, and except in the genital region where 

 they are slightly developed, and in somites IV and V, in which they 

 make their appearance, is thickly enveloped in chlorogogue cells wLh 

 largely conceal the dorsal vessel also. ' 



As in all membei-s of the genus hitherto described, the vascular 

 system presents a well-developed integumental plexus on theTateral 



