170 Some Change* in Crustacean Nomenclature, 



1. The Linna3an genus Cancer is abandoned by Weber, and 

 among its dissevered parts we find the genus Alphem for that 

 group of crabs which three years later Fabricius kept as typical 

 of Cancer. Alphas Weber therefore may be considered a 

 synonym of Cancer, and, as it is a synonym, it can no longer 

 be employed for the macruran gen vis which has so long served 

 as the type of the Alpheida\ 



2. The name Crangon appears first in Weber attached to the 

 four species "of shrimps which were later called Alpha* * by 

 Fabricius, viz., ararus, famulus, rapax and malabaricits ; all but 

 the last were nom'nia nnda at that time, and therefore maldbaricd 

 is the type of Crangon. In place of Crangon Fabricius 1798, we 

 may use Crago Lamarck,* type Crago vulgaris (= Centre,- rrangon 

 Linnaeus). 



3. In Weber we find the genus Homarus, which is usually 

 attributed to Milne Edwards 1837. t As Weber used Alphni* 

 to include the typical crabs, abandoning Cancer altogether, so he 

 used Homarus for the lobster, crayfish, and other typical species 

 of Astacas Fabricius 1775 and abandoned Astacus altogether. 

 Instead of regarding Homarus Weber as a synonym of Astacti* 

 Fabricius, it is desirable to allow both names to stand each with 

 the type later assigned to it, viz, Homarus gaminarus (Linna>us) + 

 and Astacus astacus ( Linnaeus ). This is in accordance with 

 Canon XXVI of the A. O. U. code, which follows an earlier and 

 similar canon promulgated by the British Association. 



4. Parthenope Weber 1795 contains six species, fornicata, 

 gifaffa, longimana, regina, lar and dubia. Of these the second 

 and last three were nomina nuda at that date, leaving fornirata 

 and longimana the only valid species. Parthenope Fabricius has 

 up to this time been limited according to the specification of its 

 type by Leach 1814, as horridu Linnaais, a species included by 

 Weber not in Parthenope but in a list of doubtful species of 

 Cancer listed in his introduction. Strictly speaking, the lim 

 itation of Parthenope took place at an earlier date than thVt of 

 Leach. In 1801 1| Lamarck formed the genus Maja by uniting 

 Inachm and Parthenope, giving the type of the latter group as 



*Syst. Anim. sans Vert., 159, 1801. 



fHist. Nat. Crust., II, 333, 1837. 



t Milne Edwards, Hist. Nat. Crust., II, 333, 1837. 



\ Latreille, Consid. sur les Crust., 422, 1810. 



1 Syst. Anim. sans Vert, 154, 1801. 



