448 Mr. J. Blackwall on the Structure, Functions, CEconomy, 



transmitted to me living specimens of Salticus tardigradus, cap- 

 tured by her at Balham, in Surrey. A female, which I had placed 

 in a phial, spun a sac of fine white silk in June, and attached to its 

 inner surface a lenticular cocoon of delicate white silk of a loose 

 texture measuring |^rd of an inch in diameter, in which she 

 deposited 35 spherical eggs of a pale yellow coloui-, not aggluti- 

 nated together. 



M. Koch's figure, number 1130, is stated to represent a female 

 in the text, but a male is delineated in the plate. 



30. Salticus formicarius. 



Salticus formicarius, Latr. Gen. Crust, et Insect, torn. i. p. 124; 



Sund. Vet. Acad. Handl. 1832, p. 200; Koch, Die Arachn. 



B.xiii. p. 33. tab. 438. fig. 1101, 1102. 

 Attus formicarius, Walck. Hist. Nat. des Insect. Apt. t. i. p. 470. 



Dr. Leach has remarked, in the Supplement to the 4th, 5th 

 and 6th editions of the ' Encyclopsedia Britannica,' article Annu- 

 losa, that Attus [Salticus) formicarius is found, though rarely, 

 in Scotland; consequently I have included it in this catalogue, 

 but I have not succeeded in procuring a British specimen. 



Family Thomisidce. 

 Genus Thomisus, Walck. 



31. Thomisus hrevipes. 



Thomisus brevipes, Hahn, Die Arachn. B. i. p. 30. tab. 8. fig. 25 ; 



Walck. Hist. Nat. des Insect. Apt. t. i. p. 503 ; Blackw. Linn. 



Trans, vol. xix. p. 122. 

 Xysticus hrevipes, Koch, Uebers. des Arachn. Syst. erstes Heft, p. 25. 



I have occasionally met with adult females of this species under 

 stones in fields adjacent to woods at Oakland, near Llanrwst. 

 The only male I ever captured resembled the female in colour ; 

 but, though the digital joints of its palpi were very tumid, the 

 palpal organs were not developed, indicating that it had to un- 

 dergo its final change of integument before it arrived at maturity. 



As there does not appear to be the least necessity for adopting 

 the genus Xysticus, proposed by M. Koch, to which he has trans- 

 ferred this and some other species of British Thomisi, I have 

 deemed it expedient to adhere to the generally received method 

 of arrangement in this instance. 



32. Thomisus cristatus. 



Thomisus cristatus, Walck. Hist. Nat. des Insect. Apt. t. i. p. 521 ; 



Latr. Gen. Crust, et Insect, tom. i. p. Ill; Sund. Vet. Acad. 



Handl. 1832, p. 217. 

 pini, Hahn, Die Arachn. B. i. p. 26. tab. 8. fig. 23. 



