82 Mr. C. Spence Bate on the 



anticipated, have been thought probable since our knowledge 

 of the development of My sis. 



The desirability of our knowing the form, structure, pro- 

 gressive growth, and parentage of these young forms is clearly 

 demonstrated in Claus's recent beautiful work on the Genea- 

 logical Foundation of the Crustacean System, p. 54, in which 

 he says, " In relation to the transformation of Galathea, 

 which, on account of the half-bent tail, was placed with the 

 Anomura, but, however, belongs decidedly to the long-tailed 

 crawfish, unfortunately but little hitherto has become known 

 to us. Couch has given an illustration, which has been re- 

 produced by Bell, of a young recently hatched Galathea-X&xYdij 

 which confirmed the observation previously made by Rathke 

 (Archiv f. Nat. 1848, p. 241), that it, as well as the larva of 

 Pagurus^ represents a higher degree of development than does 

 the Zoea of Carcimis mcenas, since, besides the two anterior 

 double-branched pairs of legs, there is also a third jaw-foot 

 present in the form of a still simple numerously jointed appen- 

 dage — in contrast to the CY&h-Zoea, which, as far as known 

 in all groups and families of the Brachyura, want the posterior 

 jaw-foot as an acting limb. There appears consequently the 

 character of the prawn-Zbea in the GaIatIiea-\a,Yva, though in 

 a weakened form, which, taken altogether, according to bodily 

 structure, formation of antennae, and jaws, might be placed 

 among the long-tailed crawfish." 



I do not know Eathke's figure of Galathea alluded to by 

 Claus ; but if it be not more clearly determined than the one 

 referred to of Couch, it cannot be relied on for guidance as to 

 the form of the animal, and is therefore valueless for general 

 classification. 



I have examined, and have in my possession, the young of 

 both British and exotic Galathem^ taken from the parent im- 

 mediately after being hatched, which show that the larva of 

 Galathea in its stage of development resembles Porcellana 

 and Pagurus in having conditions which, as far as my 

 own observation goes, are common to the Anomurous group. 

 In development they are in advance of the Zoece of the 

 Brachyura, but not so far as those of the Macrura. The 

 Zoece of LatreilUaj Homola, Doripe^ and even Dromia have 

 not been determined. I include Dromia among the unde- 

 termined forms ; for the figure that Claus has given with a 

 query as the young of Dromia approaches, according to my 

 experience, nearer to the larva of Gelasimus than to any 

 of the Anomurous group, while the larva of TricMa^ a 

 genus nearly allied to Dromia^ assimilates to the Anomuran 

 stage. 



