Yorkshire Naturalists at Harwood Dale. 



Notable omissions are H. virgata and H. pidchella. Seven 

 species of Hyalinia were observed : — Hy. cellaria, Harwood 

 Dale and Breaday Gill ; Hy. alliaria and Hy. crystallina, Har- 

 wood Dale, Cloughton Moor, Breaday Gill, Hackness, Lindhead 

 Barn ; Hy. fulva, common everywhere ; Hy. piira, Harwood 

 Dale and Breaday Gill, fairly common ; Hy. nitida and Hy. 

 jiitidula, Breaday Gill, not common. Dead shells of Vitrina 

 pellucida were found in all these localities. Cochlicopa liihrica 

 was generally distributed. Carychium minimtim occurred 

 sparingly in Harwood Dale and the Cloughton Moor ravine, 

 and Balea perversa was abundant under the flat stones on the 

 top of a moorland wall at the head of Breaday Gill. This 

 species lives in a similar situation in Forge Valley ; in fact, such 

 appears to be its normal habitat in the Scarborough district. 

 It is most numerous — in clusters of a dozen or more — where the 

 wall is overhung by trees, this position probably affording more 

 moisture and favouring the growth of mosses, though Balea is 

 not, as far as I have seen, taken amongst moss nor on the most 

 thickly-covered stones. Pupa cylindracea was found with Balea 

 and also in Harwood Dale and on the moraines above Lindhead 

 Barn. A dead specimen of Clausilia lami7iata was found on 

 a wall in Harwood Dale, and one alive at Hackness on Ash 

 branches with one Buliminus obscurus and an abundance of 

 Clausilia perversa. One specimen of Vertigo edentula was taken 

 on Cloughton Moor. 



Slugs were exceptionally numerous, Ariofi hortensis, A. 

 circumscriptus , A. minimus, A. ater, Limax agrestis, L. Icevis 

 occurring everywhere, the first two together even in the wildest 

 parts ; Limax maximus was found in Breaday Gill, Z. arhorum 

 at Breaday Gill and Cloughton Moor, Arion suhfuscus in Har- 

 wood Dale and Breaday Gill, and Lijnax ciiiereo-iiiger in the 

 Cloughton Moor ravine, Breaday Gill, and on the escarpment 

 near Silpho Brow. Several specimens of Succinea putris were 

 swept by the coleopterists near Lowdales. 



There were few opportunities of finding freshwater species. 

 Velletia lacustris was very abundant in a pond near the Mill 

 Inn, in striking contrast to its extreme rarity in known localities 

 near Scarborough and in East Yorkshire generally. Twenty- 

 four were counted on one small branch and another larger 

 harboured over fifty. Pisidium pusillu7n was taken in the same 

 pond. Aficylus fluviatilis was found in small streams near the 

 Mill Inn and above Lindhead Barn, but apparently does not 

 occur in the larger streams, Lownorth Beck, Lowdales Beck, 



rgod. June 3. 



