REPORT ON THE AMPHIPODA. 247 



and "Spec. 3. Gammarus sitclienda" n. s., fig. 28, a-r., from the Island of Sitcha, inter- 

 mediate between Gammarus locusta ? and Oammams pulex and fasaiaius, Say. This 

 Boeck unites to Gammarus locusta, in regard to which species Brandt makes vigorous 

 eflfbrts to disentangle the confusions of the early writers. Under /3 with '' the inner branch 

 of the third uropod not even, or at most, a quarter as long as the outer, and often only 

 rudimentary, he places "Spec. 4. Gammarus atchensis," n. s., fig. 29, a-c, from Atoha and 

 Unalaschka ; "Spec. 5. Gammarvs loeustoides," n. s., fig. 30, a-c, from Ayan on the sea 

 of Okotsk; "Spec. 6. Gammarus ochotensis," n. s., fig. 31, a-c, from the same sea, and 

 " Spec. 7. Gaumiarus lomjkauda," n. s., fig. 32, a-c, allied to Gammarus dentatus, Kr0yer, 

 with which Spence Bate was inclined to unite it, while under the name of Melita dentata, 

 Kntyer, Boeck actually does so. 



A form from the Sea of Okotsk, which Brandt at first took for an Ampliithoe , he decides to place 

 in Dana's genus Allorcliestes as AUorchestes ochotensis, n. s., fig. 27, a-f., near to " AvqiMthoe 

 Marionis," Milne-Edwards. To AUorrhestes he also refers' Ordiestia grandicornis, Kr0yer. 

 Both should rather be referred to Hijule, Rathke. (See Note on Rathke, 1837.) Of the 

 telson of his species Brandt says, " Der Schwanzanhang besteht aus zwei abgerundet- 

 rhomboidalen, kurzeu, am Ende verdickten, mit einzelnen Dornchen versehenen Pliittchen," 

 thus affording an additional reason against applying the name AUorchestes to species with an 

 tjntire telson. In the Brit. Mus. Catal., 1862, on Plate la, for " 4. 0. Ochotensis.," should 

 be read 4. A. Ochotensis., for "6. 0. Ochotensis.," 9. 0. Ochotensis., and for "9. 0. 

 brevicornis.," 6. T. brevicornis. 



Among the Laemodipoda Brandt gives, from Nichta Bay iu the Sea of Okotsk, Caprella affinis, 

 n. s., like Cajirella linearis, Johnston (1835), but differing from it in the greater size of the 

 hands of the first gnathopods, which are more than half the size of those of the second 

 gnathopods, and in the much longer, untoothed, penultimate joint of the hinder pair of 

 feet, which appears longer than the two jjreceding joints. Caprella nichtensis, n. s., he 

 compares with Caprella lobata, Miiller (Kroyer, Voy. en Scand. pi. 25. fig. 3). Mayer does 

 not find himself able to identify either of these two unfigured, briefly described species, or 

 even to decide whether they belong to the genus Caprella at all. 



Spence Bate in his B. M. Catalogue founds a new genus, Brandtia, for a species which he refers 

 to as " Gammarus latissimus, Brandt, Voi/ar/e de Middendorff," with " Hah. (Arctic Asia ?) 

 Voyage de Middendorff." The figures and description were taken by Sp. Bate from speci- 

 mens which Professor Brandt had sent to the Museum at Paris, but the species Gammarus 

 latissimus was instituted by Gerstfeldt in 1858, and was found by Maack in the Angar;\ at 

 Irkutsk. 



185L Costa, Achille. 



March. 



Fauna del Eegno di Napoli. 



Genere Callisoma ; Gallisoma, (Costa). 



The genus Callisoma, named in 1840 by 0. G. Costa, is now described : — "Generis characteres 

 essentiales. Anfennx superiores capite paulo longiores, validissimaj, subulatte, pedunculo 

 crassissimo, bisetse : inferiores graciles, longiusculai. Pedes quatuor antici gracOes haud 

 oheliformes, secundi longiores. Epimera articuli quarti thoracici clypeiformia, inferne 

 postice producta. Characteres naturales. Corpus compressum, breviusculum, e latere 

 subovatum. Antennee superiores breves, capite idem ac inferiorum pedunculo paulo longiores ; 

 pedunculi articulo primo crassissimo, duobus sequentibus lobgitudine et crassitie decrescen- 

 tibus ; setis duabus pluri-articulatis, seta primaria crassa subulata, pedunculo breviore ; 

 .secundaria minuta gracili. Pedes primi paris graciles, manu simplici unguiculata termiaati : 

 secundi anterioribus fere similes at longiores : trium pariura posticorum articulo primo 



