BRACHYURA. 389 



into spine nor seen in dorsal view) and of the anterior borders of the meropodites 



of the walking legs (serrate). 



Lambrus (Rhinolambrus) contrarius (Herbst), 1804 A. 1, p. 266. 



Localities : Coral reefs, Gulf of Manaar, four specimens (b, c, g, h) ; pearl banks, 

 Gulf of Manaar, four specimens (a, e, i, d) ; Chilaw Paar, one specimen ( /*). 



Description:- ()yg. ?. (J)yg?. (c)yg.<?- (<*)yg.<?- ()yg<?- (f)yg-S- (j)i<J. 



C.l. (rost, included) . 11'50 24-00 950 18-00 19*75 2275 38-75 



C.b.-f-C.l 0-89 0-92 0-84 0'92 0-90 0"89 0-93 



Ch.l.-=-C.l 2-17 2-30 2-18 2\36 2"34 2'58 2"86 



The growth-changes in ratio Ch.l. -J-G.l. will be noted. 



Lambrus (Rhinolambrus) longispinis, Miers, 1879 A.l, p. 266. 



Localities : Pearl banks, Gulf of Manaar, eight specimens ; coral reefs, Gulf of 

 Manaar, three specimens. 



Description : The specimens are all young four of them males. The C.l. of the 

 latter varies from 10'5 to 16 ; the scanty evidence suggests that no great change in 

 the ratio Ch.l. -f- C.l. accompanies this growth. There is at this size no very obvious 

 establishment of sexual dimorphism. 



(a) yg ? (*) yg- ? (<) yg- ? 00 yg- ? () yg S- (/) yg- S is) yg 6* ( /( ) yg- 6* 

 C.l. (rost, included) . 12-25 12'25 12-50 19-25 



C.b.-^C.l 0-94 0-98 0"92 1-00 



Ch.l.H-C.1. . . . 2-14 2-16 2-06 2'39 



The present specimens agree closely with Alcock's example and confirm his belief 

 that the species is more nearly related to L. contrarius, Herbst, than to L. validus, 

 DE Ha an. Variability is low among the above examples for most characters ; the 

 shape of the rostrum is an exception. The latter is acutely pointed in most of the 

 examples, narrowing rather suddenly a short distance in front of the eyes ; in one 

 specimen no such sudden narrowing occurs ; in another there are two small lateral 

 lobes near the apex ; other examples are intermediate. 



Lambrus (Rhinolambrus) pelagicus, Ruppgll, 1830 A.l, p. 2G7. 



Localities : Coral reefs, Gulf of Manaar, one specimen (young ? ) ; off Mutwal 

 Island, one specimen (adult S). 

 Description : 



Young? . . . C.l. = 7-50; C.b.H-C.l.= 1-00; Ch.l.^-C.l. = 2-63. 



Adult 6* . . . C.l. = 16-00; Cb.-=-C.l. = T02 ; Ch.l.-=-C.l. = 3-16. 



Lambrus (Aulacolambrus) hoplonotus, Adams and White, 1848 A.l, p. 273. 



Localities : Pearl banks, Gulf of Manaar, four specimens (a, b, e, g) ; coral reefs, 

 Gulf of Manaar, three specimens (c, d,f). 



