408 Mr. E. J. Miers on some 



Museum collection in -vvliich the carapace is armed with six 

 more or less distinctly developed frontal teeth (including those 

 forming the inner angle of the orbit), with a tooth or spine 

 in the middle of the lateral margins, and which are not marked 

 with red spots or reticulating lines. 



The variations in the development of the teeth of the 

 frontal margins cannot, in my opinion, be considered to con- 

 stitute specific distinctions ; and those of the arms vary in 

 number and shape, even on the right and left sides of the same 

 specimen. Dr. Heller has shown {I. c. p. 350) that M.- 

 Edwards's description of the position of the outer maxillipedes 

 of T. ferruginea when closed is incorrect ; and there is no 

 difference in this respect between T. ferruginea from the Eed 

 Sea and specimens of T. dentifrons from Australasia given by 

 the Paris Museum to the British-Museum collection. Dr. Hil- 

 gendoif (Crust, in Van der Decken's 'Reisen in Ost-Afrika,' iii. 

 p. 76), while acknowledging the insufficiency of the characters 

 derived from the form of the teeth, and of the arms and front, 

 seems to think that Rlippell may have been right in separating 

 the species by their colour-variations only. A careful exami- 

 nation of the large series in the Museum collection has shown, 

 however, that two very distinct forms may be distinguished, 

 and always recognized, by the following characters : — In the 

 first (and probably the commonest) the lateral marginal teeth 

 of the carapace are acute, the hand is suhcristate above and 

 beloio and hairy on its outer surface ; in the second, the lateral 

 marginal teeth are blunt or even almost obsolete, the hand is 

 longer, rounded on its upper margin, and naked on its outer 

 surface. 



To the latter, T. ferruginea, belong the specimens from the 

 Gulf of Akaba, a very large series (upwards of sixty indivi- 

 duals) from the Dadalus Hhoal, Red Sea, collected by Col. 

 Playfair, specimens from the Gulf of Suez [MacAndrew), 

 Mauritius [Lady Cole), and Samoa Islands {Whitmee), also 

 probably the specimens from Tahiti and the Sandwich Islands 

 referred by Dana to T. cymodoce, those from the Cape of 

 Good Hope described by ]\PLeay as T. subinteger, and those 

 from the Marquesas to which Jacquinot and Lucas have 

 assigned the name of T. miniata. To the former species, 

 which I have designated T. cymodoce, belong specimens in the 

 Museum collection from the Daedalus Shoal {Playfair), Gulf 

 of Suez [MacAndrew), Ceylon [Holdsivorth) , Pliilippine 

 Islands [Cuming), Fiji Islands [H.M.S. ^Herald''), specimens 

 from Australasia from the Paris Museum named T. dentifi-ons, 

 Latreille, and the examples from the Marquesas described by 

 Jacquinot and Lucas as T. hirtipes. 



