TERRESTRIAL ACARI OF THE TYNE PROVINCE 1 7 



1. Dorsal trichomes arcuate clavatc ... ... clavattivi. 



Dorsal trichomes erect ... ... ... ... 2 



2. Dorsal trichomes fusiform clavate ... ... jjcxaliim. 



Dorsal trichomes much inflated, not acuminate 3 



3. Dorsal trichomes without stalk above the socket biillatum. 

 Dorsal trichomes shortly stalked ... ... suhra<;iit)i. 



5. Enemothrombium clavatum, Geo. 66, 67. 



E. densipapillnin^ Berl. 



Fond of sphagnum, though by no means confined to 

 it. Easily distinguished by the curved trichomes. 



Yorkshire, Scotland. 



6. Enemothrombium pexatum, K. 67. 



Ottofiia conifera^ Geo. 



Eiie?nothrombiiwi calycigenim^ Berl. 



Dorsal trichomes septate, the distal segment smaller, 

 smooth and bluntly pointed or slightly wedge 

 shaped. 



Yorkshire, Ireland, Scotland. 



7. Enemothrombium bullatum, Geo. 67. 



E. rasum, Berl. 



This species, like the next, has much inflated 

 trichomes which mostly collapse in drying or when 

 mounted in balsam. They are everywhere con- 

 tiguous on the living animal, so that the dorsum 

 under the lens appears to be areolate and 

 glabrous. 



Usually found in water or near it. Yorkshire. 

 Cumberland (Varty-Smith). Scotland. 



8. Enemothrombium subrasum, Berl. 67. 



Ottonia ignofa, Geo. 



Generally in water or wet sphagnum. After death 

 only a few of the larger trichomes preserve their 

 form. The basal segment appears to be longi- 



