of the Fishery Board for Scotland. 477 



of Podon leuckartii, and the lower branches are provided with the same 

 number of seta3 ; but the upper branches differ in being furnished with an 

 additional seta on the penultimate joint — one of the setae springs from the 

 middle of the joint and the other from its distal end — this branch, there- 

 fore, carries seven instead of six setae (fig. 26). 



The caudal spines are moderately stout, and straight, but smaller than 

 those of Podon leuckartii (fig. 25). 



Habitat. — Firth of Clyde, not very rare. It may be readily dis- 

 tinguished from Podon leuckartii by having an additional seta on the 

 upper branches of the antennae and by the caudal spines being smaller 

 and straight. 



Podon polyphemoides, Leuckart — a species considerably smaller than 

 the other two — is, like Podon intermedins, provided with seven setae on 

 the upper branches of the antennae, but the end joints of both branches 

 are distinctly shorter than the preceding joints ; the supplementary seta 

 on the penultimate joint of the upper branches springs from near the 

 distal end instead of near the middle of the joint. The caudal spines 

 are also smaller. Probably Podon leuckartii has sometimes been 

 mistaken for this species.* 



Order EDRIOPHTHALMA. 

 Sub-Order AMPHIPODA. 



Many species belonging to the Amphipoda have been observed in tow- 

 net gatherings, in dredged material, and in the stomachs of fishes 

 examined during the past year, but only some of the rare forms are 

 recorded here. 



PONTOPOREIID^E. 



Bathyporeia norvegica, G. 0. Sars, occurred in a tow-net gathering 

 collected in Aberdeen Bay on September 4th, 1901. Argissa hamatipes 

 (Norman) was also observed in some of the gatherings collected off Aber- 

 deen during the past year. 



Phoxocephalid^e. 



The only species belonging to this family which may be noted is the 

 Phoxocephalus oculatus, G. 0. Sars; it was obtained in a tow-net 

 gathering collected about 22 miles to the north of the Shetland Islands on 

 May 17th, 1901. 



Ampeliscid^:. 



Several species of the Ampeliscidae have been observed, not only in 

 gatherings collected with the tow-nets and dredge, but also in the 

 stomachs of fishes, with whom they appear to be a favourite kind of 

 food. The following species were observed: — Ampelisca macrocephala 

 has occurred in gatherings from the Firth of Forth, from off Aberdeen, 

 and from the Shetland district. Ampelisca assimilis has been obtained 

 in gatherings and in fishes' stomachs from the Firth of Forth and 

 Collieston, Aberdeenshire. Ampelisca spinipes was obtained in 

 dredgiugs from the Firth of Forth (with parasites attached) and in the 



* All the three species of Podon mentioned above have recently been obtained in some 

 tow-net gatherings from the Firth of Clyde collected for the most part in April and May 

 and in July and August 1901 ; P. leuckartii was obtained in the spring gatherings, but not 

 in those collected later ; while the other two species were observed in these later gather- 

 ings only. 



