NUDIBRANCHS OF THE VANCOUVER REGION 1 63 



Family Dorididae Phanerobranchiatae. 



Branchiae forming a dorsal tuft, but not retractile into a pocket. 

 Two spermatothecas. 



Section Polyceridae. 



Shape generally limaciform with appendages. Teeth differentiated. 

 Radula often narrow. 



Genus Laila (MacFarland.) 

 Laila MacFarland, Proc. Biol. Soc, Washington, 1905, p. 46. 



Body depressed; frontal and lateral margins narrow, set with club- 

 shaped papillae; rhinophores retractile, clavus perfoliate, branchial 

 plumes few, tripinnate, non-retractile into a sheath; tentacles blunt, 

 canaliculate. A flattened submarginal ridge on each side of the anterior 

 end of the body just behind and above the tentacles. 



No labial armature nor mandibles. Radula not narrow, the rachis 

 with a single series of flattened spurious teeth; first pleural tooth slender, 

 hook-like, the second large, the remaining lateral teeth (10-13) smaller, 

 flattened. 



Glans penis armed. 



The genus was proposed for the reception of the following form. It is 

 allied to the genera Triopa Johnston and 755a Bergh, but differs from the 

 first in the presence of spurious teeth on the rachis of the radula. From 

 755a it differs in the absence of mandibles, and from both in the presence 

 of the submarginal flattened ridge or lobe. 



Laila Cockerelli (MacFarland). 



Laila cockerelli MacFarland, Proc. Biol. Soc, Washington, Feb. 1905, 

 p. 46; Bull. Bur. Fisheries, Washington, 1905, p. 134, pi. XXVIII; 

 Cockerell and EHot, Jour. Malac, XII, 1905, p. 43. 



Body. — 'The body is elongated and fairly high (about as high as wide) 

 a little more sharply rounded posteriorly. The mantle margin while 

 prominent is nowhere wide and the foot protrudes behind. The dorsum 

 is slightly arched and fairly smooth with a few, about 36, small rounded 

 tubercles. The mantle carries a number of conspicuous club-shaped 

 papillae which may reach a length of 5 mm. and a breadth of i mm. at 

 the top and even when contracted are i mm. long. They are closely 

 set and arranged in a number of oblique rows 3 or 4 in each, decreasing 

 in size from the inner ones outwards and each papilla has an axial sup- 

 porting core of spicules. 



Colour. — ^The general body colour is stated and figured by MacFarland 



