ZOOLOGY 2i 



species occur in the area, most of them abundantly. Nine of these have 

 been added to the Hst since the visit of the British Association in 1906. 

 The Foss, once a navigable river, has been allowed to silt up, and being 

 unscoured by any fast-flowing current, has become a most profitable 

 centre of study for all kinds of fresh-water biology, but its Mollusca are 

 particularly important, some thirty-four species having been recorded 

 from that river alone, practically within the confines of the city itself. 



Insects. 



The areas previously described are all noteworthy hunting-grounds. 

 The Lepidoptera have been studied very carefully and continuously, so 

 that our records are very full. The reproach in the Handbook of 1906 

 about the neglect of the so-called Microlepidoptera no longer holds. Of 

 butterflies, the Peacock, the Comma, and the Wall are rare, and the 

 Wood Argus does not occur. About thirty-three species are recorded 

 as having occurred, but this number includes, of course, the very 

 occasional wanderers, such as the Clouded Yellow and the Camberwell 

 Beauty. It is interesting to note that, as a rule, the annual arrival of 

 our Painted Lady butterflies is about five to seven days after the record of 

 the insect's appearance upon the South Coast, that is, usually, during the 

 first week in June. The White-Letter Hairstreak, after being unnoticed 

 for many years, has again been found in the north of our district. The 

 Duke of Burgundy occurs in Newton Dale, just out of our area, and the 

 Brown Argus on the Wolds at Millington. 



Of moths, the following have been given to me as the * best things ' to 

 be obtained in the localities mentioned. At Askham Bog : Acronycta 

 leporma, Leucania impudens, Ccenocalpa lignata, Collix sparsata and 

 Scotosia vetulata. At Strensall and Sandburn : Palimpsestis or, Cybosia 

 mesomella, Agrotts agathina, Eurois occulta, Xanthia paleacea, Acidalia 

 straminata, Triphosa dubitata, Eucosmia undulata, Epione vespertaria 

 [parallelaria). This common has the distinction of being the one locality 

 in England for Epione vespertaria, although odd specimens have been 

 taken once or twice in other places. At Sledmere : Abraxas tilmata, 

 Asthena blomeri. At Pickering : Trichiura crateegi, Ortholitha bipunctaria. 

 At Millington : Parasemia plantaginis, Ino geryon. At Cropton : Aplecta 

 nebulosa, Lithomoia solidaginis, Xanthorhoe tristata. At Hovingham and 

 Garrowby : Eupithecia pusillata. At Wass : Plusia interrogationis . At 

 Gilling : Venusia cambrica. 



The Coleoptera of York have been investigated for many years, and 

 the records extend back for more than a century. Amongst the pioneers 

 was Archdeacon Hey, who began in 1840, and whose records include much 

 that is of the greatest interest, particularly with respect to the water 

 beetles of Askham Bog. But the pools of Askham are not all what they 

 were at the time of the visit of the British Association in 1906. They have 

 not been drained, as have so many pieces of fenland which the naturalists 

 of a former generation knew, but have silted up with the accumulated 

 dead leaves of the trees growing round them, and these in the pools them- 

 selves have formed a thick, souring mass very destructive to insect life, 



