AQUATIC LARVAE OF FLIES IN THE HULL DISTRICT. l8l 

 SIALID&. 



Sialis lutarius. Barmston Drain at Hempholme. Pond 

 Springhead. River Hull above Beverley. 



PERLID^E. 



Perla bicaudata. River Hull just below the Weir at 

 Hempholme Lock. (Very scarce). 



EPHEMERID^E. 



Ephemera vulgata. West Beck near Corps Landing. 

 Hutton Beck. Beck near Cranswick. Barmston Drain at 

 Dunswell. (Found living in burrows in the mud). 



Chloeon dipterum. Generally distributed, being not 

 nearly so local as E. vulgata. (Found on aquatic plants and 

 stones). 



Baetis fluminum. Cave Beck under stones to which 

 they cling tenaciously. 



MARINE ZOOLOGY IN THE EAST RIDING, 1904. 



The following have been taken on the Holderness coast 

 during 1904. In the fishing cobles at Hornsea, May 28th, 

 Crustacea : — Hoplonyx cicada (Fabr.), Callisoma hopei A. 

 Costa, Idotea marina (Linn.), Idotea linearis (Penn.), Jcera 

 albifrons Leach, Hippolyte varians (Leach). In crab pots, 

 Hornsea, August 8th, Polynoe imbricata Linn., Pedicellina 

 cernua (Pall.) on whelk shells, and Phoxichilus spinosus 

 (Mont.) ; with the mollusca, Lacuna crassior (Mont.) common, 

 L. pallidula (da Costa), Cingula semistriata (Mont.) abundant. 

 Modiolaria discors (Linn.) was washed up alive at Kilnsea 

 (sea side) on August 16th ; several specimens of Syndosmya 

 alba (Wood) were found alive on the tide mark at Aldborough 

 during the same month, and dead specimens of Syndosmya 

 tenuis (Mont.) were taken on the river side at Kilnsea. 



Eurydice pulchra Leach from Well Creek is an addition 

 to the Humber Crustacea; and Haustorius arenarius (Slabber), 

 the sand furrow maker, from Aldborough, adds another 

 species to the East Riding list. The common estuarine 

 schizopod, Neomysis vulgaris (Thompson), was abundant 

 during August in the ditch which forms the western boundary 

 of Westlands, Hedon. 



T. Petch. 



