292 MR. BELL, HOILE CARCINOLOGIC^ ; 



Ilia Nucleus, Auct. Testa minute conferte granulosa, granulis niajoribus distantibus 

 instructs. 



Cancer Nucleus, Linn. Syst. Nat. 1042. 20. Herbst, i. p. 87. t. 2. f. 14. 



Leucosia Nucleus, Fabr. Suppl. p. 351. Latr. Hist. Nat. Crust, vi. p. 116. 



Ilia Nucleus, Leach, Zool. Misc. iii. p. 24. Roux, Crust, de la Mediterr. t. 8. f. 1-8. Edw. Reg. Anim. 



de Cuv., Crust, t. 25. f. 2; Hist. Nat. Crust, ii. p. 124. 

 Hab. ad oras maris Mediterranei. 



Ilia rugulosa, Roux. Testa glabra, sparsim granulosa, antice kevi. 



Ilia rugulosa, Roux, /. c. t. 8. f. 9-12. Edw. /. c. p. 125. 

 Hab. cum praecedente. 



I refer to tbe admirable figures by Roux, in his ' Histoire des Crustaces de la M6diter- 

 ran£e,' for a clear exposition of tbe characters of these two species, the only ones of the 

 genus yet known. I cannot believe that Ilia punctata of Edwards belongs to this genus 

 at all. The figure in Herbst of Cancer punctatus, on which he has partly founded it, is 

 undoubtedly that of a species of Myra, as is shown even by the form of the pedipalps, and 

 it may possibly be that of M. carinata of this memoir. The species provisionally named 

 Ilia Mariannes by Herklotz, and figured by him from a specimen in the Louvain Museum, 

 is obviously not an Ilia. The foot-jaws and abdomen it appears were wanting in the spe- 

 cimen, so that it would be difficult to state what may be its generic relation ; but it has 

 the appearance of Myra, or still more of Myrodes ; or it may possibly offer a new generic 

 type, as suggested by the author above-named. 



Genus Persephona, Leach. 



Char. Gen. — Testa ovalis vel orbicularis, depressa, dentjbus tribus ad partem posteriorem armata, regio- 

 nibus pterygostomianis angulatis. Orbita trifissa. Fossce antennarioe transversae. Pedipalpi externi 

 caule exteriore paulo dilatato, sensim angustiore, ad' apicem interne truncato. Pedes antici robusti, 

 testa haud bis longiores ; reliqui articulis ultimo et penultimo compressis. Abdomen Maris seg- 

 ments a tertio ad quintum, — Fcemin^e a quarto ad sextum coalitis. 



The characters of this genus and those of the species named by Leach were so im- 

 perfectly given by him, in the ' Zoological Miscellany,' that Milne-Edwards, not having 

 access to the specimens themselves from which they were derived, was fain to content 

 himself with simply translating them, being wholly unaware that they referred to a 

 previously well-known species, and in fact he gave to that species the generic name of 

 Guaia. I have, I believe, been able successfully to unravel this complication by an 

 examination of the numerous specimens in the British Museum, to which Leach's names 

 were attached. 



Persephona Guaia, Bell. Testa ovata, sparsim tuberculata, angulo pterygostomiano 

 obtusissimo, spina media postica lateralibus paulo altiore. 



Cancer punctatus, Browne, Hist. Jamaica, i. t. 42. f. 3. 



Cancrejo tortuga, Parra, Descrip. &c. t. 51. f. 2. 



Cancer Mediterraneus, Herbst, ii. t. 37. f. 2. 



Persephona Latreillii, Leach, Zool. Misc. iii. p. 22. Desmar. Cons, sur les Crust, p. 168. 



