SCOTTISH HAIRWORMS in 



across the sea, then a land-bridge must be assumed in spite 

 of what geologists may say. 



Bibliography of the Outer Hebridean Water-Beetles. 



Dale, C. W.— " Entomology in the Isle of Harris, etc.," Enl. Mo. Mag., xix., 

 237, 8, 1882, 3. 



Walker, J. J. — " Coleoptera of Stornoway, N.B.," il>i(L, xxxi. (Ser. 2, vi.), 

 1S2, 1895- 



Champion, G. C— "Coleoptera at Stornoway, Lewis," iljitl., xxxvii. (Ser. 2. 

 xii.), 279, 1901. 



SCOTTISH HAIRWORMS {NEMATOMORPHA, 

 GORDIIDyE), THEIR OCCURRENCE. HABITS, 

 AND CHARACTERISTICS; WITH A KEY 

 FOR THE DISCRIMINATION OF THE 

 SPECIES RECORDED FROM BRITAIN. 



By James Ritchie, M.A., D.Sc, The Royal Scottish Museum. 



Contents. 

 I. General Notes. 



(a) Habits and Life-history. 

 {b) Diagnostic Characters, 

 (c) Mode of Preservation and Examination. 

 II. Key to the Characters of Hairworms {Gordiidce) recorded from 

 the British Isles. 

 III. Description and Distribution of Scottish Hairworms. 

 IV. Literature. 



I. General Notes. 



(a) Habits ajid Life-history.— Yound in most fresh-water 

 areas, in ponds, ditches, and streams, less frequently amongst 

 damp vegetation, Hairworms are familiar to the majority 

 of field naturalists. In the adult stage, in which they are 

 generally recognised, they are of great length and remarkable 

 slenderness, and are tinted a rich deep brown verging 

 almost on black. They possess a thick cuticle, which renders 

 them exceedingly hard and tough ; and the writer has a 

 vivid boyhood recollection of an unsuccessful endeavour to 

 sever, by pressure with a splinter of wood, a fine specimen 



