ATYLUS SWAMMERDAMII. 247 



antennas are subequal, and about half the length of the 

 animal ; the peduncle of the superior pair is scarcely more 

 than half the length of that of the inferior ; the flagella 

 of both pairs of antennae have the articuli nearly as 

 broad as long, each articulus in the superior pair being 

 furnished with a single hair, and one short auditory cilium. 

 The first pair of legs are smaller than the second, but 

 neither of them are very strong. The legs are rather 

 short, and the three posterior pairs have the fingers 

 generally directed backwards. The caudal appendages 

 are nearly of the same length, the penultimate being a 

 little the shortest; in the last both branches are of 

 the same length, styliform in shape, and free from hairs. 

 The central tail-plate is about as broad as long, some- 

 what truncate, and cleft from the apex nearly to the 

 base. 



This species is evidently the same as that described by 

 Prof. Milne Edwards, from the coast of Morbihan. Spe- 

 cimens have been sent to us from the Moray Frith, by the 

 Rev. G. Gordon, in compliment to whom the species was 

 named, previously to our ascertaining it to be identical with 

 A. Swammerdamii of Milne Edwards. We have also taken 

 it in Plymouth Sound. The specimen named Dexamine 

 Loughrini in the " British Museum Catalogue," after Mr. 

 Loughrin (in consideration of the services which he, a 

 coast-guardsman of Polperro, had done for science in 

 collecting marine animals), was taken in the rock-pools 

 at the mouth of that harbour, where the shore suddenly 

 dips into many fathoms of water. Upon reconsideration, 

 we look upon it, however, to be but a variety of this 

 species, differing chiefly in the length of the second joint 

 of the peduncle of the superior pair of antennae, the 

 length of the central caudal plate, and the general colour 

 of the animal. 



