260 



H. P, KJERSCHOW AGERSBORG. 



gigantic size for a nudibranch ! It is matter of common knowl- 

 edge, however, that the fauna of the North American Pacific coast 

 attain not only a large size, but are in fact very abundant and 

 diversified. (Vide: Kjerschow Agersborg, 1920.) 



Large specimens of this genus also occur in the vicinity of Puget 

 Sound Biological Station, Friday Harbor, Washington. Thus dur- 

 ing the summer of 1913 a collecting party from the station found 

 on the shore of Shaw Island (not very far from Canoe Island) a 

 large specimen which must have measured about 200 mm. in length. 

 To the writer's knowledge no one identified the specimen at that 

 time. It was conveniently classed D. arborcsccncc. 



FIG. i. Photograph of Dendronotus giganteus O'Donoghue, dorsal view. 



During the summer of 1921 I again visited the Puget Sound 

 Biological Station. On July 20 I found a very fine specimen of 

 Dendronotus between the logs of the floating dock of the station 

 (Figs. 1-4). Upon examination it was found to fit perfectly to 

 the description of O'Donoghue for D. giganteus. It measured 140 

 mm. long by 60 mm. high by 40 mm. broad. The foot was 90 mm. 

 long and 40 mm. wide at its widest part. This specimen was kept 

 alive in the laboratory for three weeks. During this time it did 

 not feed, as far as I know, on anything. I tried to feed it on 

 crustaceans, echinoderm gonads, coelenterate tentacles, green algae, 



