25 



i888. Laireillia valida, Henderson, (Jhailenger^ Macrura, Reports, 



vol- 27, p. 24. 

 1893. Latreiilia valida, Stebbing, History of Crustacea, p. 137, 



pi. 5 (from de Haan). 

 1899. Latreiilia pciiiiifera, Alcock, Journ- Asiat. Soc. Bengal^ 



vol. 68, p. 168. 

 1901. Latreiilia poinifera, Alcock, Indian Decapod Crustacea, 



p. 71, pi. 7, fig. 27. 

 It should be observed that Major Alcock himself introduces his 

 species with the remark that it is "very closely related to /-.- 

 ekgans, Roux." The specific name which he gives to the Indian 

 form is highly appropriate to the penultimate joint in the last pair 

 of legs, it being, as he says, " plumed on both sides so as to 

 exactly resemble the vane of a feather." This character is equally 

 conspicuous in the specimen forwarded to me from the Cape, 

 but when originally describing this form before I had seen Major 

 Alcock's figure and description, I persuaded myself that it was 

 identical with de Haan's L. valida, and that the remarkable 

 feathering had not attracted that author's attention in a dried 

 example or had been by some accidental circumstance removed. 

 In point of fact, de Haan's artist does give a fringe of setules to 

 the joint in question. But the same joint is drawn by S. I. 

 Smith very distinctly feathered on both sides' in a United States 

 specimen of L. clegans, and the feathering at least for one margin 

 is shown with equal clearness in the figures given by Lucas for a 

 Mediterranean example of the same species. De Haan distin- 

 guishes L. clegans from the Japanese form by its not having a 

 dorsal spine on the gastric region, by the greater length of the 

 eye-stalks and frontal spines, by the fourth segment of the pleon 

 being bispinose in the middle, and by the thinner legs. Roux 

 only had female specimens, and de Haan does not claim to have 

 examined any but one from Roux' own collection, so that 

 Heller's statement that de Haan observed the male also seems to 

 be a mistake- But de Haan's statement that the composite fourth 

 segment of the pleon in the female of Z.i^/^^fi/w IS bispinose in the 

 middle must also be mistaken. Milne-Edwards, Lucas, Herer, 

 agree in stating that the two pairs of spines on this segment are 

 lateral or sublateral. The lower pair seem to be minute. A dis- 

 tinction depending on the comparative lengths of eye-stalks and 

 frontal spines cannot well be trusted, since they are apparently 

 not a little variable. In a detail figure Smith represents the 

 spines as quite unsymmetrical. Any difference in the thickness 

 of the legs between the forms here compared seems unappreci- 

 able, so that for specific distinction nothing remains but the 

 presence or absence of two or three insignificant-looking spines 

 and the greater or less length of the setae on a particular joint- 



The South African specimen has the frontal spines extending 

 along the basal joint of the eye-stalk just to the thicker terminal 



