RATHBUN— MARINE BRACHYURA 205 



The sinuses between the frontal teeth are deeper than in the figure cited ; the last 

 lateral spine is about twice as long as the preceding. In a smaller specimen (C. 1. 

 12 - 8 mm.), the lateral spine is 2tj times as long as the preceding. 



34. Portunus (Achelous) granulatus (Milne Edwards) (Plate 15, fig. 10). 

 Lupea granulata Milne Edwards, Hist. Nat. Crust., i. 1834, p. 454. 

 Neptunus (Achelous) granulatus Alcock (4), p. 45 (part); not Amphitrite gladiator, 



var., de Haan, 1837, pi. 18, fig. 1. 



Portunus (Achelous) granulatus Rathbun, 1906, p. 871, pi. 12, fig. 2. 



Cargados Carajos, 30 fms., Sta. B 3 ; 1 $, 1 ?. 



Two closely allied forms have been combined by myself and others under the specific 

 name "granulatus." The true "granulatus," I believe, is that figured in my Hawaiian 

 bulletin (loc. cit.). while the other species is that figured by de Haan, Fauna Japonica, 

 Crust., pi. 18, fig. 1, as a variety of Amphitrite gladiator. The shape of the chelipeds, 

 maxillipeds and legs is the same in both, and that of the carapace nearly the same. 



The chief differences are as follows : 



(1) In gramdatus, the granules cover nearly the whole of the carapace, the smooth 

 sulci between the areoles being narrow; in orbitosinus the granules are in j)atches separated 

 by broad smooth areas. 



(2) In granulatus, the sinus between the first antero-lateral tooth (the orbital 

 tooth) and the next tooth is as wide as the succeeding sinus ; in orbitosinus the first sinus 

 is much smaller than (usually half as wide as) the second sinus. This is well shown in 

 de Haan's figure. 



(3) In granulatus, the suborbital sinus is narrow and very deep, much deeper 

 than its greatest width; in orbitosinus the sinus is shallower, approximating an equilateral 

 triangle. 



(4) In granulatus, the abdomen of the $ is triangular, after the 3rd segment*; 

 in orbitosinus the margins of the abdomen after the third segment are strongly 

 sinuous and the 6th segment is widest at its middle f. 



35. Portunus (Achelous) orbitosinus, sp. nov. (Plate 15, fig. 11). 



Amphitrite gladiator, var., de Haan, Fauna Japon., Crust., 1837, p. 65, pi. 18, 

 fig. 1. 



Cargados Carajos, 30 fms., Sta. B 15; 1 $, 1 ? : 30 fms., Sta. B 17; 1 $, 1 $: 30 fms., 

 Sta. B 23; 2 $, 2 ?. Amirante, 32 fms., Sta. E 5; 1 ? : 33 fms., Sta. E 8; 1 ? : 34 fms., 

 Sta. E 9 ; 2 juv. Seychelles, 31 fms., Sta. F 2 ; 1 juv. : 44 fms., Sta. F 6 ; 1 ? : 34 fms., 

 Sta. F 8 ; I $ : 37 fms., Sta. F 9 ; 1 ?. 



For description, see under preceding species. 



This appears to be a larger species than P. gramdatus, and also a commoner one 



in the western Indian Ocean. $ Sta. B 23, C. 1. 22 "6 mm., C. b. 33 - 3 mm. The largest 



P. granulatus handled is an ovigerous £ from the Caroline Islands, measuring 17 x 24 mm. 



(A. Milne Edwards, loc. cit., gives 19 x 28 mm.). 



* As stated by A. Milne Edwards, Arch. Mus. Hist. Nat., x. 1861, p. 344. 



t The abdomen accompanying de Haan's fig. 1, pi, 18, though labelled " £ ," is that of a 9 • 



