40 



MARINE AND FISHERIES 



5 GEORGE v., A. 1915 



with respect to the armature of the legs. I have not been able to find a similar 

 condition of armature figured, although it may occur in many of the well-known 

 species. The small size of the abdomen renders examination difficult in most cases. 

 From the foregoing facts it has seemed necessary to form a new genus for the 

 reception of this species. The number of genera in the group of the Caprellids is 

 large and the majority are monotypic. It seems impossible, however to avoid 

 creating a new one without doing violence to the principles laid down by Dr. 

 Mayer for classification in this group. The classification that he has built up is 

 doubtless as sound as any that could be devised. 



I should like to call attention to the way in which the various genera in this 

 group result from a ringing of the changes on a comparatively small number of 

 characters. Nearly all possible combinations of these characters are to be found. 

 This is analogous with the way in which among chemical compounds a large 

 proportion of the possible combinations of certain radicles or elements may be 

 obtained. I believe that the analogy is due to the fact that in each case the basis 

 is a chemical one. 



I propose to name the genus in honour of Dr. P. Mayer, to whom we owe the 

 major part of our knowledge of the Caprellidae. His monographs will long form 

 the foundation of any work in this group. 



Mayerella, gen. nov. 



Inferior antennae. — Flagellum two-jointed. 



Mandible. — Palp three-jointed, terminal joint with a single bristle, which is 

 terminal in position. 



Maxilliped. — Inner plate half as long as outer and with three bristles. 



Branchiae. — On third and fourth segments of peraeon. 



First and second pereiopods. — Two-jointed, terminal joint short and with 

 three bristles. 



Third pereiopod. — Three-jointed, terminal joint with four bristles. 



Abdomen or pleon. — In female, with two pairs of bristles but without legs. 

 In male, with one pair of unjointed legs and behind these a series of bristles on 

 each side, representing another pair of legs; each leg bearing from five to seven 

 bristles and terminating in a series of hooked teeth. 



M. limicola, sp. nov. (Pis. V and VI, figs. 1-12). 



Surface of body smooth, with scattered minute bristles. Length (exclusive 

 of appendages), of male 5^ mm., of female 4f mm. 



The proportionate lengths of the segments of peraeon are roughly, 



Male 

 Female 



Head + 1st 



2.5 



2 



6th -I- abdomen 

 3 

 2.5 



