456 E. RAY LANKESTER. 



exuberance in the production of spines and spinules^ wliicli 

 exhibits individual variation. 



As stated by M. M. -Edwards and Houvier, C. granulatus 

 is more richly beset with fine hairs than is C. quadratus. 

 These hairs are not represented in Mr. Albany Hancock's 

 drawings reproduced in our plates, but are present in Norman's 

 specimens both on the eye peduncles and other appendages 

 as well as on the carapace. 



The difference in the form of the eye-stalks is very striking 

 — those of C. granulatus presenting a well-marked corneal 

 area which is absent from those of C. quadratus, and also 

 being more robust, rounded in cross-section instead of 

 flattened, and beset with numerous spinules. The row of 

 spines on the inner margin is not so regular as in C. 

 quadratus (see PI. 33, figs. 5 and G). The rostrum also is 

 larger and more robust, and provided with coarser spinules in 

 C. granulatus than in C. quadratus, and projects con- 

 siderably further forward than the eye-stalks, whereas in 

 C. quadratus it is not so long as the eye-stalks. 



In both species there is a well-developed extra-orbital 

 spine on the frontal margin of the carapace on each side (PI. 

 34, fig. 7, sjJ., and text-fig. 10, sp.). But this spine is 

 much larger and more coarsely denticulate in C. granu- 

 latus than in C. quadratus. It appears to be subject to 

 variation in C. quadratus, as it is larger in the lower 

 specimen drawn in our text-fig. 10 than in the upper, 

 which is taken from the figure of M. M. -Edwards and 

 Bouvier. It seems to me that the prominence and great 

 size of this extra-orbital spine, forming with the base of the 

 rostrum an almost cup-like cavity on each side of that 

 structure, as shown in A. Milne-Edwards' drawing of a 

 mutilated specimen devoid of eye peduncles ('Travailleur,' 

 loc. cit., pi. xi, fig. 5), is eminently characteristic of C. 

 granulatus as compared with C. quadratus. 



Distribution. — Mediterranean and North Atlantic. 



Species 3. — Cymonomus Normani, n. sp. (1903). 



As C. granulatus in all characters except the following. 



