REV. O. P. CAMBRIDGE ON BRITISH SPIDERS. 437 
marking occupies the fore half of this band, and is of a dark brown colour, paler a 
its hinder extremity, the posterior portion of the band being white. 
The legs are white, tinged with yellow and pale yellow-brown, and boldly striped, 
spotted, and blotched in parts with rich brown and black. 
The abdomen, which is of an oval form, and somewhat depressed, has the entire central 
length óf its upperside (in the form of an elongate lozenge or diamond shape) of a dark 
brown colour; the fore half of this has a broad margin of a bright rust-red, reaching 
quite to the sides and front of the abdomen, where it becomes of a whitish hue; the 
hinder half is nearly black (except its posterior extremity, just above the spinners, which 
is white); and from the outer limits of the black there issue some short stripes of the 
same colour, the stripes being formed by a series of almost confluent spots, which de- 
crease in size towards the extremity of the stripe. Some irregular spots of a yellowish 
colour form a sort of interrupted line between the central brown lozenge-shaped marking 
and the surrounding surface. The sides and underside of the abdomen are of a dull whitish- 
yellow colour: the former are longitudinally rugulose ; and the latter has a broad central 
longitudinal band of yellow brown. 
The falces hàve their bases and extremities, in front, of a dem rich black-brown, the 
central portion being white. 
This fine and handsome spider was found by myself on Bloxworth Heath, on a mild, 
bright, sunny morning, in December 1870; it was sitting and, apparently, sunning itself 
at the extremity of a furze shoot. It is just possible that this may be but a variety of 
T. sabulosus (Koch); but as, among the numerous examples I have found of that species, 
I have never seen any one approaching the present in colour and markings, I am induced 
to describe it as a distinct species. 
Genus PHILODROMUS (Bl.). 
PHILODROMUS AMBIGUUS. j 
Philodromus ambiguus, Bl. Ann. & Mag. Nat. Hist. for Sept. 1867. 
pallidus, Bl. Brit. & Ir. Spid. p. 93, pl. v. fig. 56. 
Araneus margaritatus, Clerck, p. 130, pl. vi. t. ii. 
Philodromus margaritatus, W estr. Ar. Suec. p. 454. 
Aranea jejuna, Panzer, Faun. Germ. 83. 21. 
Artamus jejunus, Koch, Die Arachn. xii. p. 83, Taf. 415. figs. 1015- ee 
. Philodromus jejunus, Cambr. Zoologist for 1863, p. 8597. 
It appearing to Mr. Blackwall that the spider recorded as Philodromus pallidus (Brit. 
& Ir. Spid. loc. cif.) is distinct from P. pallidus (Koch), with which he had before con- 
sidered it identical, he has conferred upon it the specific name of ambiguus. P. jejunus, 
at first sight so remarkably distinct-looking a spider, is evidently only a variety of 
P. ambiguus; Y can find no structural difference in the adult males of the two; but the 
leading distinction in colour and markings is constant and striking: it appears as if, in 
P. jejunus, all the markings were eliminated except a few tolerably symmetrically dis- 
posed jet-black spots and blotches, while the ground-colour is very nearly pure white. 
Hitherto I have not met with any intermediate varieties; and the two distinct ones 
