3IO 



SCIENCE-GOSSIF. 



Amaurobius fenestralis Stroem. (Ciniflo 

 atrox Bl. ) 



Length. Male 7.3 mm., female 8.4 mm. The 

 size of this spider is subject to much variation. 



Cephalo-thorax yellowish-brown, the caput being 

 much darker. Legs pale brown, indistinctly annu- 

 lated with a darker hue. The abdomen has at its 

 anterior part a dark blackish-brown marking. This 

 spider may be found during the winter months under 

 the loose bark of decaying trees in dry situations. It 

 is very common, and generally distributed throughout 

 the country. 



Amatirobius similis Bl. (Cinifio si//ii/is Bl.) 

 See fig. IV. 



Length. Male 10.5 mm., female 12.6 mm. 



This species is similar in general appearance to the 

 last, but may be distinguished by the following dif- 

 ferences :— The abdomen is of a colder grey tint, the 

 dark marking on its fore part being less distinct and 

 more broken up. The radial joint of the male palpus 

 has a black curved apophysis (shown in fig. IV.) ; the 

 corresponding projection in A. fenestralis Stroem. is 

 paler, and neither so much curved nor so narrow. 

 This spider is even more common than the last, and 

 may be found beh'nd boards in outhouses, under 

 floors, or in openings in brick walls, around which 

 latter it spins a mass of flocculent web of a bluish 

 tint. I have noticed that the percentage of males 

 in this species is far less than in the case of A. fenes- 

 tralis Stroem. 



Aiaaurobius ferox Walck. [Ciniflo ferox BX.) 



Length. Male 10 mm., female 13 mm. 



This species, which is found in similar situations 

 to A. similis Bl. , may be distinguished by its dark 

 sooty colour, and also by the form of the pa' pal 

 organs. In this species the pale lobe, which is 

 present in the other species oi Amaurobius, is greatly 

 developed and of a brilliant white colour. The female 

 is a very powerful spider, and is one of our largest 

 species. 



Family DVSDERIDAE. 



This family may be distinguished from all others 

 (except Scytodidae) by the species it contains possess- 

 ing but six eyes. The spiracular openings are four in 

 number. 



GENUS DYSDERA LATR. 



This genus may be distinguished by the position 

 of the eyes, which are arranged in the form of a 

 horseshoe, with, its open side ■ in front. The tarsal 

 claws are two in number. Two British species only 

 are at present known. 



Dysdera cambridgii Thor. (Dysdera ery- 

 thrina Bl.) 



Length. Male 12 mm., female 12.5 mm. 



Cephalo-thorax bright reddish-brown, legs reddish- 

 yellow, abdomen pale yellowish-grey, falces of the 

 same colour as the cephalo-thorax and extremely 

 prominent. This is a very striking and distinct 

 spider, and is found, though not commonly, under 

 stones and decayed bark. 



Dysdera crocota C. Koch. Fig. V. 



Length. Male 12.2 mm., female 12.8 mm. 



This spider is exceedingly like the last in structure 

 and habits, but may be distinguished by the form of 

 the male palpal organs, which, in this species, end 

 in two distinct prominences. It is rather uncommon. 

 Tlie female is represented on fig. V. 



GENUS HAliPACTES TEMPL. 



Tliis genus may be distinguished from Dysdera by 

 the position of the eyes, which form almost a circle. 

 The tarsal claws are three in number. Only one 

 species has been found in Britain. 



Harpaetes hombergii. 



Length. Male, 6 mm., female 6.3 mm. 



Cephalo-thorax. Dark red-brown. Legs. 

 Pale yellowish-brown, indistinctly annulated with a 

 darker hue. Ardomen. Brownish grey. This 

 spider is not uncommon under loose bark and stones 

 in dry situations. 



GENUS SEGESTRIA LATR. 



This genus may be at once distinguished from the 

 preceding genera by the position of the eyes, which 

 are arranged in three groups of two each, the groups 

 being placed in a transverse line. The tarsal claws 

 are three in number. 



Segestria senoculata Linn. Fig. VI. 



Length. Male 6.3 mm., female 10.5 mm. 



Cephalo-thorax. Dark brownish-grey. Ab- 

 domen. Yellowish-grey with a series of diamond- 

 shaped blackish patches along the centre of its upper 

 surface. The palpal organs are very simple, con- 

 sisting of a bulb gradually drawn out into a fine 

 point. This is not an uncommon sjiider under loose 

 bark. The female is represented on fig. VI. 



Segestria bavariea C. Koch.- 



Length. Male 7 mm., female n mm. 



This spider is very similar to S. senoculata Linn., 

 but may be distinguished by being more hairy, and 

 by the bulb of the male palpal organs being drawn 

 out more abruptly. It is very rare. 



Segestria florentina Rossi. 



Length. Male 18 mm. 



This extremely rare spider may be at once dis- 

 tinguished by the brilliant green colour of the falces. 



GENUS SCHOENOBATES BL. 



The position of this genus is very doubtful, as it 

 appears to bear a close relationship to the Theridiidae, 

 but differs in the possession of six eyes only. 



Schoenobates ivalkeri Bl. 



Length. Male, 3-1 mm. 



Cephalo-thorax red-browYi, with white hairs. Ab- 

 domen mottled brown, also clotlied with white hairs. 

 It is extremely rare. 



[NOTK. — In consequence of a printer's error, ante 

 page 239, line 14, second column, read "many," 

 instead of " any." — Ed. S. G.] 



( To be continued. ) 



