47 -A 8 Proceedings of the Royal Irish Academy. 



This species is closely related to the genus Podarke, differing only in the 

 greater development of the dorsal lobe of the foot. 

 Mature specimens were found in January. 

 Habitat.— Blacksod Bay — Dredged in 6-8 fms. Ballynakill Harboue — 



Dredged on 2 occasions, in 2-12 fms. 

 Distribution. — British Isles; Scandinavia; North Sea ; France; Spain; 

 Mediterranean. 



Castalia punctata (0. F. Miiller). 



1908. Castalia punctata. MeTntosh, p. 121. 



This species is common on the shore, living under stones, and in Laminaria 

 roots. 



Habitat.— Blacksod Bay — Found on the shore on 4 occasions. Dredged 

 on 2 occasions in 4J-5-J fms. Clew Bay — Dredged on 7 

 occasions, in 5i-19 fms. Ballynakill Haebour — Dredged 

 in 1-3 fms. Dredged 2 miles S.W. of Shark Head, in 

 33 fms. 

 Distribution. — British Isles; Scandinavia; Western Baltic; Iceland; 

 Azores ; Gulf of Gascony. 



Castalia fusca (Johnston), typ. 



1908. Castalia fusca. Mcintosh, p. 127. 1862. Castalia aurantiaca. 



Sars, p. 90. 1890. Castalia aurantiaca. Michaelsen, p. 61. 



This species is very common on the shore, living under stones and in 



Laminaria roots. It is also frequently taken in the dredge, in shallow water. 



In this species the terminal pieces of the setae are provided with very 



long coarse teeth, giving them a characteristic appearance, and the tip is 



simply hooked, not bifid. 



Mature specimens were found in May. 



The Castalia aurantiaca described by Sars (torn, cit.), as recorded by 

 several Scandinavian observers, seems to be this species. I have examined 

 specimens thus named by Michaelsen from Kiel (torn, cit.), and they are 

 typical examples of Castalia fusca. Two well-marked varieties of this species 

 are described below, which may eventually prove to be distinct species. 



Habitat. — Blacksod Bay — Found on the shore on 17 occasions. Dredged 

 on 3 occasions, in 1-6 fms. Clew Bay — Shores of Clare 

 Island, in Lithothamnion. Dredged on 4 occasions in various 

 parts of the Bay, in 5-17 fms. Ballynakill Harbour — 

 Dredged on 2 occasions, in 1-8 fms. Found once on the 

 shore. 

 Distribution. — British Isles ; Scandinavia ; Western Baltic ; France ; 

 Madeira ; Mediterranean, 



