150 Schibdte's Specimen 



species of Gammarus, such as brevicaudatus and Othonis, M.- 

 Edw.* 



NlPHARGUS. 



Ordo Amphipoda — Familia Gammari. 

 Oculi nulli Antennae superiores inferioribus longiores, flagello 

 appendicular! minuto, biarticulalo. Pedes ultimi paris stylo 

 interiori brevissimo, exleriori valde elongato, biarticulato. 



Niphargus Slygias. 



Elongatus, surama altitudine a dorso segmenti tertii ad infe- 

 riorem epimeri marginem quintuplo longior, subcompressus, 

 crassitie maxima segmenti tertii altitudinem baud sequante, 

 lsevis, carinis dentibusque carens omnino. Color niveus. 

 Long. 5 — 7 lin. 



The commonest among the proper cave animals, is a species, 

 which, not confining itself to the columns in the depths of the 

 caves, is found wandering about on the walls, on the columns 

 near the outlet, which have become blackened by the torches, 

 and also along the frequented paths and roads ; and it is the 

 only animal among those treated of here, which was known 

 before, though imperfectly only. It is a white crustacean of the 

 family of Oniscidce, and has been figured by Koch under the 

 name of Pherusa alba.f He had, however, defective specimens 

 only, without antennae or the last pair of abdominal legs, and had 

 to rely on the want of eyes for his generic character. On refer- 

 ring to Koch's work on the subject, ErichsonJ has subsequently 

 added some remarks, derived from his examination of better pre- 

 served specimens in the Berlin Museum, concerning the appen- 

 dage to the last pair of abdominal legs, and the number of joints 

 in the flagellum of the antennae, which he rates at eight. As this 

 is all the information we have hitherto possessed as to this animal, 

 I have availed myself of the present opportunity of entering into 

 a detail of its structure. 



According to M. Koch's division of the family of Oniscidce 

 (Cloportides, Lat.), founded on the structure of the last pair 



* Annal. des Soc. Nat. torn. xx. p. 373. Milne-Edwards mentions that the 

 appendicular flagellum is three-jointed. 



t Deutschlands Crustaceen, Myriapoden und Arachniden, 34stes Heft. 1840. 

 $ Archiv fur Naturg. 1841, vol. ii. p. 252. 



