On the Systematic Arrangement of British Spiders. 95 



This impression seems to belong to the Labyrinthodon, but 

 differs somewhat from those of the Bunter sandstone of Cheshire, 

 appertaining probably to another species. I propose therefore to 

 call it the L. Lyelli. 



Another impression which seems to partake of a batrachian 

 character is common at Green Mill ; but the animal which has 

 caused it having been apparently of small size, the steps are 

 rather indistinct. In this case the same difference obtains between 

 the impress of the fore and hind step as marks the foregoing form. 

 In the hind footmark three toes usually occur, two of which are 

 longer than the sole of the foot, and the other about the same 

 length. Traces of two other toes are in some instances visible ; 

 but these are small, and occur one on the inner side and the 

 other on the outer side of the impression. The whole length of 

 the foot is commonly less than an inch, and its breadth about 

 ^ of an inch. About \ of an inch in front of the larger impres- 

 sion are seen the marks of the fore-feet, which are in the form 

 of indents ; but in some cases they present a foot-like marking 

 resembling the fore-step of the Labyrinthodon. The length of the 

 stride is about 3 inches, and the space between the impressions 

 on the right and those on the left side is about 2 inches, distances 

 somewhat similar to those in the preceding batrachian ; and the 

 form of the step is such as to show some analogy between these 

 two forms. The characters are however not such as to lead to 

 the conclusion that the impression belongs to the Labyrinthodon ; 

 and I propose to term this form of step Batrichnis, giving to this 

 impression the name of B. Stricklandi, after Mr. Strickland, who 

 has at different times noticed the ichnolites of Dumfries-shire. 



XI. — A Catalogue of British Spiders, including remarks on their 

 Structure, Functions, (Economy and Systematic Arrangement. 

 By John Blackwall, F.L.S. 



[Continued from p. 44.] 



62. Clubiona lapidicolens. 



Clubiona lapidicolens, Walck. Hist. Nat. des Insect. Apt. t. i. p. 598. 

 lapidicola, Latr. Gen. Crust, et Insect, torn. i. p. 91 ; Sund. 



Vet. Acad. Handl. 1831, p. 139 ; Hahn, Die Araehn. B. ii. p. 9. 



tab. 40. fig. 100. 



The claim of Clubiona lapidicolens to a place among British 

 spiders rests on the authority of Dr. Leach. See the Supplement 

 to the 4th, 5th and 6th editions of the 'Encyclopaedia Britan- 

 nica/ article Annulosa. 



