OF NORTHWEST COAST 

 OF NORTH AMERICA 



SYNOPSIS OF SUBFAMILIES AND GENERA 



I. Subfamily 



The penial bulb consists of a muscular cushion containing muscular 

 strands mostly radiating from the base of the bulb, but also running in 

 a peripheral manner. Among these muscular strands are often found 

 numerous glandular cells arranged in sets, which open onto the basal 

 surface of the penial bulb. The sperm-ducts penetrate the bulb but 

 the glands in the bulb do not open into the ducts. Setae sigmoid in 

 four fascicles on each somite. No dorsal pores. 



An atrium and atrial glands generally present. Dorsal vessel rises 

 posterior to clitellum and is furnished with cardiac gland. One 

 pair of sperm-sacs and a single median ovisac. Head-pore generally 

 at the apex of the prostomium. Nephridia pluri-lobed, with wide 

 closely wound canals ........................... i. Mesenchytrceus Eisen. 



II. Subfamily ENCHTTR^EIN^E. 



No large compact penial bulb, only one or more smaller or larger 

 papillae, consisting of a number of unicellular glands arranged in sets, 

 in which the individual cells radiate in a feathery or fan-shaped man- 

 ner from a common point on the base of the papillae. A few muscular 

 strands penetrate between the glandular sets, radiating from the base 

 of the papillae to the parietes or body-wall situated laterally to the ven- 

 tral ganglion. Sperm-ducts open independently of the penial papillae, 

 though in their immediate vicinity. Never any atrium. Setae always 

 straight when present. Nephridia not pluri-lobed. No intestinal di- 

 verticles. Peptonephridia glands present or absent. No dorsal pores. 



Four fascicles of setae in each somite and more than one seta in each 

 fascicle ............................................. 2 . Enchytrceus ( Henle) . 



No fascicles of setae. Setae single or even entirely absent in many 

 somites .................................................. 3. Michaelsena Ude. 



