438 REV. O. P. CAMBRIDGE ON BRITISH SPIDERS. 
represented by P. ambiguus and P. jejunus are very seldom (here at least) found in the 
same locality. The former is not rare on Scotch firs; the latter in orchards, on lichen- 
eovered apple-trees; and in both cases they bear a striking resemblance to the lichens 
with which these trees are severally clothed. I have received the var. jejunus from J. C. 
Dale, Esq.. of Glanville's Wootton, Dorset, by whom it was also found among lichens on 
an apple-tree. If (as I think) P. ambiguus (Bl.) is the same species as the Araneus mar- 
garitatus (Clerck), this latter name will, of course, take precedence of the former in any 
systematic arrangement. 
PHILODROMUS FALLAX. 
Philodromus fallax, Sund. Vet.-Akad. Handl. 1832, p. 226; Westr. Ar. Suec. p. 461. 
deletus, Cambr. Zoologist for 1863, p. 8564. 
. Dr. Thorell of Upsala, who is well acquainted with the Swedish types of most of the 
spiders described by his countrymen C. J. Sundevall and N. Westring, assures me that 
the Philodromus deletus (Cambr.), of which I have forwarded him examples, is identical 
with P. fallax (Sund. and Westr.). 
This spider is a striking instance of the adaptation of colouring in animals to the sur- 
rounding surface of the ground upon which they live. It is not rare on the bare sand- 
hills at Bournemouth, Hampshire, though not easy to be seen except when in motion, 
and instantly lost sight of as soon as stationary, owing to its remarkable similarity to 
the colour of the sand. The adult male has not yet been discovered, although I have 
searched carefully for it at various periods of the year. 
PHILODROMUS ELEGANS. 
Philodromus elegans, Bl. Ann. & Mag. Nat. Hist. 3rd ser. vol. iii. p. 92. 
fallax, Westr. Enum. Ar. p. 51. 
——— decorus, Westr. Ar. Suec. p. 459; Bl. Brit. € Ir. Spid. p. 94, pl. v. fig. 57. 
elegans, Cambr. Zoologist, 1859, p. 6497 ; Zoologist, 1860, p. 7946. 
The adult male of this handsome species is also a desideratum. In addition to the 
New Forest locality, I have received a single example (an immature male) from Dr. 
Knaggs, captured on Shirley Heath in 1860. 
PHILODROMUS HIRSUTUS. 
Philodromus hirsutus, Cambr. Zoologist for 1863, p. 8565. 
Originally found, though very rarely, at Bloxworth. I have since received numerous 
examples (but all immature) from Wicken Fen, near Cambridge, where they were cap- 
tured and kindly sent me by Mr. William Farren in April 1869. It is nearly allied to 
Thanatus striatus (Koch, Die Arach. Bd. xii. p. 92, fig. 1022), a species I have never 
seen; but Dr. L. Koch does not consider it identical. 
Genus SPARASSUS. 
SPARASSUS ORNATUS. 
Sparassus ornatus, Walck. tom. i. p. 583; Bl. Ann. & Mag. Nat. Hist. for Sept. 1, 1869. 
If the discovery of the adult male of this species should show it to be structurally 
