21 



posterior to clitellum, with chloragogen glands. Spermathecae without 

 diverticles, opening into the intestine. Sperm-ducts three or four 

 times as long as the funnels, which are sigmoid. No atrial and no 

 accessory glands. One set of penial glands confined to penial bulb. 

 A pair of long sperm sacs 



and an ovisac. Neph- s -^ 



ridia large, plurilobed. / \ 



Lymphocytes of medium V J 



size, eosinophile ellipso- ^ ' 



idal. Color of formalin 

 specimen white. 



Locality. Unalaska, 

 Aug. 10, 1899. Collected 

 by Prof. W. A. Setchell. 

 Found under moss. 



Characteristics, One 

 of the smallest species 

 investigated. Specimens 

 found in August not fully 

 developed, clitellum want- 

 ing. No atrial glands 

 could be seen, and no ac- 

 cessory glands. Lymph- 

 ocytes extremely charac- 

 teristic, being strongly 

 eosinophilous, with red 

 granules surrounded by a 

 pellucid, uncolored zone. 

 Cells in the tissue too 

 small to allow of a more 

 detailed description. 



FIG. i. Mesenckytrceus unalaskce. 



MESENCHYTR^EUS ASIATICUS sp. nov. 



pi. xi, fig. 4; and text-figs. 2 and 3. 



Definition. Length about 14 mm., width i mm. or .9 mm. 

 (contracted specimens). Somites 54. Setae: laterals, 2, 2, 2, 2, 2, 

 2 * 2, 3, 3, 2, 3, 3, 2, 2, etc. ; ventrals, 4, 4, 4, 4, 4, 5, 4, 6, 5, 5, 

 o, 4, 4, 4, 3, 3, etc. Prostomium not much pointed, with head-pore 

 half way between apex and somite I. Clitellum prominent, IX to 

 XIII. Sexual papillae quite prominent. Brain posteriorly more or 

 less deeply emarginated. Dorsal vessel rises behind clitellum. Sper- 



