ALASKA NEMERTEANS 83 



tions. It was restless in confinement, and an active swimmer. It was 

 found under a stone near low water mark at Hot Springs, near Sitka. 



EXPLANATION OF PLATES. 



The colored plates (I to VI) are reduced from colored sketches 

 made, with a few exceptions, from the living animal. They were com- 

 pleted after the return of the expedition and have been retouched, and 

 in some instances entirely redrawn, by Mr. A. H. Verrill. Every 

 effort has been made to make the colors and the form of the body as 

 natural as possible. 



In the figures on the plates the following reference letters are used : 



ap, attachment of proboscis. 

 bg, buccal glands. 

 bg' , accessory buccal glands. 

 bl, blood lacuna. 

 ble, epithelium of same. 

 bin, basement layer. 

 br, brain. 

 bv, blood vessel. 



bva, anastomosis of lateral vessels. 

 cc, ciliated canal of cerebral sense or- 

 gan. 



cgl, cephalic glands. 

 cm, circular muscular layer. 

 cso, cerebral sense organ. 

 ct, connective tissue. 

 cugl, cutis glands. 

 dc, dorsal commissure of brain. 

 dg, dorsal ganglion. 

 dgl, secretion of cephalic glands. 

 dn, median dorsal nerve. 



e, esophagus. 



eep, epithelium of same. 



f, fibrous layer of cutis. 



gc, glandular cells of cerebral sense 



organ. 



jfl, integumental glands. 

 gp, genital pouch. 

 /, integument. 

 ic, intestinal caecum. 

 icm, inner circular muscular layer. 



ifl, inner fibrous layer. 



ilm, inner longitudinal muscles. 



in, intestine. 



Im, longitudinal muscles. 



In, lateral nerve-cord. 



m, mouth. 



mep, epithelium of same. 



nc, nerve commissure. 



nd, efferent nephridial duct. 



nep, nephridial canal. 



np, nerve plexus. 



nv, nerve. 



oc, ocellus. 



ocm, outer circular muscles. 



oep, outer epithelium of proboscis. 



olm, outer longitudinal muscles. 



ov, ova. 



pent, circular muscles of proboscis. 



pint, longitudinal muscles of proboscis. 



pn, proboscis nerve. 



ps, proboscis. 



psk, proboscis sheath or its cavity. 



rh, rhynchodaeum. 



ro, opening of same. 



smg, submuscular glands. 



sn, nerve to cerebral sense organ. 



sop, opening of ciliated canal of sense 



organ. 



vc, ventral commissure of brain. 

 vg, ventral ganglion. 



