168 bulletin: museum of comparative zoology. 



is apparently homologous with the inner circular muscular layer of 

 Carinella, Carinoma and other Paleonemerteans. Muscular 

 walls of the proboscis consist of outer longitudinal and inner cir- 

 cular layers only ; inner longitudinal layer completely wanting. 

 The two proboscis nerves conspicuous in anterior portions, but 

 farther back spread out into a plexus as usual. Basement layer 

 of the proboscis epithelium is therefore separated from the cii-cular 

 muscular layer only by the nerves or nervous jjlexus, as described 

 for L. ruhescens. 



Cephalic glands are well developed, but extend backward only to 

 the anterior portion of the brain region. 



Cutis glands form a thick and distinct layer in the midst of the 

 outer longitudinal muscles. Anteriorly they lie well toward the 

 periphei-y of this muscular layer, but sink gradually deeper until in 

 the nephridial region they lie in contact with the circular muscles 

 dorsallj' and ventrally. This condition is retained throughout intes- 

 tinal region. 



Alimentary canal. — Mouth large, elongated, situated opposite 

 posterior ends of cephalic slits. Esophagus divided into two dis- 

 tinct regions. These consist of an anterior, pear-shaped cavity, or 

 esophagus proper, and a posterior chamber, or stomach, connecting 

 with the intestine. Circular muscles about the posterior end of 

 stomach form a strong sphincter between this chamber and the 

 intestine. 



JSfepliridial canals of large size, but of limited extent ; situated 

 beside the posterior fourth of esophagus proper, and anterior third 

 of stomach, with one or two pairs of large efferent ducts. 



Habitat. — In crevices of rocks and among annelid tubes between 

 tides, San Pedro Harbor, California ; common among red algae in 

 50 fms. between San Pedro and Santa Catalina Island. 



The worms belonging to this species are remarkably hardy and 

 will live for more than a day in damp seaweed at a temperature of 

 70-80° F., and may be kept for a long time in confinement in a 

 small quantity of sea-water. Sexual products mature in Jul}^ or 

 August. 



