138 ON NEW AND RARE BRITISH ARACHNlDA. 



Hahnia pusilla, C. L. Koch. Pi. A., Figs. 7-11. 



Hahnia pmilla, C. L. Koch, Die Arachniden, 1841, Vol. VIII. , 

 p. 61, PL 270, Fig. 637, 638. 



Hahnia pusilla, Dr. A. R. Jackson, Proc. Chester Soc., Part vi., 

 No. i, May, 1907, p. 2, PI. i, Fig. 1-4. 



Adult male, length i-i8th of an inch ; female, i-i6th. 



Cephalothorax and other foreparts of a dull pale yellowish 

 brown hue, the normal indentations slightly indicated by lines of 

 a darker colour. 



The abdomen is of a whitey brown colour, suffused with a 

 darker hue and marked with indistinct oblique lines on each side 

 of the hinder part of the upper side, forming obscure chevrons. 



This small and rather obscure looking species nearly re- 

 sembles H. montana, Blackw., in size, but may be easily 

 distinguished by the darker colour and spotty markings on the 

 abdomen and cephalothorax of the latter, as well as by the form 

 of the posterior extremity of the sternum, which is broad and 

 rounded in monfana, but rather drawn out into an obtuse point 

 in pusilla. The palpi also of the males of these two species 

 differ distinctly in their structure. The spinners in montana 

 form also a longer and straighter transverse line, and the form 

 of the genital aperture is notably distinct. Examples of both 

 sexes were found at Delamere Forest, Cheshire, by Dr. A. R. 

 Jackson and Mr. W. Falconer in 1906, and were new to the 

 British list. Whether these are rightly identified with H. pusilla, 

 C. L. Koch, I do not yet feel quite satisfied. I have never had 

 an opportunity of examining an authentic type, of C. L. Koch's 

 species. That they are new to Britain is, however, quite certain. 



Robertus insignis, sp. n. Pi. A., Figs. 16-19. 



Adult male, length if lines (3 mm.). 



This species is nearly allied to R. lividus, BL, which it 

 resembles in general appearance and colour. It is a rather 

 larger spider, however, and the form and structure of the palpal 



