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Show 190 DR. W. T. CALMAN ON THE MACRUROUS [Mar. 6, what position the present forms ought to occupy within this group; and even if that question were satisfactorily answered, there would still remain room for discussion as to the appropriate name to be applied to them. It is generally agreed that Milne-Edwards's longirostris, described as coming from Algiers, but not since found there, is identical with the earlier nilotica described by Roux from the Nile. From de Man's re-examination of Milne-Edwards's types, we know that it has the carpus of the first chelipecls one and a half times as long as broad. From this Dr. de Man separates as a distinct species, under the name C. wyckii Hickson, those forms which have the first carpus at least twice as long at broad. Prof. Bouvier (Bull. Sci. France et Belgique, xxxix. p. 79, 1905) has pointed out, however, and I can confirm the statemens, that co-types of Prof. Hickson's species, from Celebes, have the carpus exactly as in the types of longirostris. Specimens received from Prof. Hickson, and preserved in the British Museum, agree very closely indeed with de Man's description of his C. nilotica, var. minahassce (also from Celebes), differing chiefly in the shorter dactylus of the posterior perseopods, that of the fourth pair being less than one-fifth, and that of the fifth pair one-fourth of the corresponding propodus. It follows that, so far as the characters of the carpal segments are concerned, C. viyckii Hickson must be regarded as a synonym of C. nilotica Roux, while C. wyckii de Man, if it is to be regarded as distinct, must receive a new specific or varietal name. Prof. Bouvier appears to regard de Man's species as merely a variety of that of Roux and Milne- Edwards (t. c, table on p. 73 ; on p. 79, however, he treats it as a separate species); and in this I a m disposed to concur, although the material at m y disposal is too scanty to enable me to form a definite opinion. At all events the specimens collected by Dr. Cunnington in Lake Nyasa and in Victoria Nyanza, while not agreeing exactly with each other or with any of the described forms, come sufficiently near to the variety gracilipes, which de M a n places under the species wyckii, and Bouvier under nilotica; and I therefore record them under the latter name. The following particulars were found to agree in several specimens from each locality, ovigerous females being compared in each case :- Nyasa.-Total length up to 21 m m . Rostrum reaching beyond antennal scale, teeth ~10_18*"S unarmed terminal part of upper edge much less than half its length ; one or two sub-apical teeth, and, occasionally, an isolated tooth a little way back from the tip. Carpus of first perasopods two and a half times as long as broad, that of second pair more than five times as long as broad. Dactylus of fourth pair one-fifth of propodus or a little over, bearing 7-9 spines ; that of fifth pair a little more than one-fourth of propodus, with about 33-38 spines. Eggs '47 X '27 m m . Victoria Nyanza.-Total length up to 25 m m . Rostrum, except in one or two cases, reaching beyond antennal scale, teeth 21~1^.21> |