450 W. F. LANCHESTER. 



the real term. In this case, however, I see no difficulty in transferring the term, whether 

 'a' or ' b,' to its proper position, the original term falling then into its proper place as an 

 intermediate. 



Turning now to the present instance, I should describe the variety as follows: — 



var. glabrous Brooks. 



Five dorsal carinae on the telson, all of which are well-developed; these carinae are 

 either sharp or tumid, and the middle three may or may not terminate in spines. This variety 

 is subdivided into 



1. Term a. Carinae sharp, with spines on the three middle ones. This I take to be 

 exemplified by the specimen figured by Brooks (Chall. Stomatopoda, PI. XIV. Fig. 5). There 

 are no true examples of this in the collection. 



2. Term b. Carinae very swollen, so as to touch one another, without spines. This is 

 the form shown under fig. 15 in my Plate. 



One male from Goidu ; length 34. 



3. Intermediates between these. Four of these show a connection, or traces of a con- 

 nection, between the median and submedian carinae (cf. figs. 8 and 9). 



Numerous examples. Goidu, Goifurfehendu Atoll ; Hulule, Male Atoll ; Fumadu Velu, 

 Miladumadulu Atoll ; Naifaro, Fadiffolu Atoll ; all from the reef Minikoi, " obtained by break- 

 ing up a coral mass from the outer reef" Miladumadulu Atoll, 3 /. South Male Atoll, 5 /. 



IX. Var. viutatus. 



The carinae are very swollen, but the middle three carry spines. 1 J" 32, and 1 ? 39, 

 Furnadu Velu, Miladumadulu Atoll; 1 ? 20, Hulule, Male Atoll; 2 /J' 27, and 21-5, and 1 ? 30, 

 Goidu, Goifurfehendu Atoll. 



X. Var. grapliuriis Miers. 



Closely similar to var. mutatus, but distinguished by the presence of sutures on the 

 abdominal terga. 



A further distinction between G. glabrous and G. graphunis, namely the presence of a 

 low median carina on the 6th abdominal segment of the latter, has also been insisted on 

 by Miers and Brooks ; this distinction is not, however, a real one. In the collection of the 

 Natural History Museum at S. Kensington are several specimens with tumid carinae, with 

 a median carina on the 6th abdominal segment, but no sutures on the abdominal terga ; 

 these specimens, having been originally labelled G. graphurus, have since been re-labelled, 

 and I think rightly, by Dr Hansen as G. glabrous. It might be urged that there is no 

 reason to regard the abdominal sutures as a more constant character than the median carina 

 of the 6th abdominal segment; but I have seen examples of undoubted G. glabrous in the 

 Natural History Museum (i.e. forms with sharply defined carinae) bearing a median carina, 

 or traces of this carina, while Henderson also (1. c. supra) remarks " in G. glaber this carina 

 is usually absent, or at most but faintly indicated " (italics mine) ; whereas I have never found 

 0. glabrous showing any signs of the abdominal sutures of G. graphurus, though indeed I 

 examined a fairly large number in the Natural History Museum in order to determine 

 whether this character of G. graphurus would present transitional stages between itself and 

 the smooth abdomen of G. glabrous. I have failed to find any such transitions, and should 

 any other carcinologist consider this single character of sufficient value to separate G. graphurus 



