NUDIBRANCHS OF THE VANCOUVER REGION I9I 



Head. — The head was inconspicuous save that it was marked off by 

 the darker line of colour passing round it as has already been noted. 



Foot. — The foot was elongated and narrow and pointed posteriorly as 

 is general in dendronotids. 



Rhinophores. — The bluntly conical perfoliate clavus of the rhinophore 

 bore from 8-10 shallow leaves which did not appear to alternate in 

 breadth. The tip of the rhinophore when extended was about 2.5 mm. 

 above the back. The rhinophore sheath is well developed and has at its 

 upper extremity four simple unbranched papillae of which the postero- 

 median is considerably longer than the rest. Low down on the side of 

 the sheath is a simple branch. 



Cerata. — The cerata of this form are quite distinctive and much more 

 simple than in the three preceding species and more so than in a small 

 specimen of D. giganteus about 9 mm. long where they already have the 

 characteristic form and arrangement. The first pair of cerata reached 

 a height of 2.5 mm. The front two pairs each consisted of three main 

 stems joining together near the point of origin and bearing from 3-5 

 simple papillae. The third pair likewise had three main trunks only one 

 of which bore papillae. The fourth pair had two main trunks one of 

 which had two papillae and the fifth pair were simple projections without 

 papillae. 



Radula. — The very pale radula had from 32-35 rows of teeth. The 

 median tooth resembles most nearly that of D. arborescens from which 

 however it differs in certain respects. It is broader, the length to breadth 

 ratio being about 5.4 whereas in the latter species it is about 13.9. Again 

 in D. arborescens the spine is almost an equilateral triangle though some- 

 what asymmetrical while in the present species it is practically sym- 

 metrical and shorter than an equilateral triangle. Then again the 

 denticles on the side of the spine are relatively much larger and extend 

 further up towards the point. The lateral teeth number from 6-8 and 

 are relatively stouter. Their ends are well curved and bear 3-6 denticles. 



Jaws. — The jaws are strong and occupy the side of the bulbus pharyn- 

 geus which measured 1.8 mm. long by 1.4 mm. wide. The processus 

 mascatorios and crista connectiva are but poorly developed while the 

 superior process is relatively quite long. 



This species is quite obviously a dendronotid but it differs in a number 

 of points from other members of the genus described and appears to be 

 sufficiently distinct to be regarded as a separate species for which I have 

 suggested the name of Dendronotus rufiis since the prorninent coloiar is 

 pink or red. 



Habitat. — ^The specimens of this species so far taken have come from 

 between Brandon Island and the head of Departure Bay and from 



