On EUROPEAN SPIDERS. 27 
2. "A History of the Spiders of Great Britain and Ireland, by 
John Blackwall’, (Part I. 1861, Part IL. 1864), is the title of the second of 
the works with the examination of which we are occupied. The work is 
published by Zhe Ray Society, and is a costly work, a small folio, with 
384 pages of text and 29 coloured plates. The author, who has long borne 
an honoured name among the zoologists of the present age, has not only 
by numerous essays of a descriptive character on the order of spiders, 
but also by important discoveries relative to these animals’ economy, their 
industry and their (outward) structure, laid this branch of zoology under 
great obligations. Since however the greatest part of BLACKWALLS pre- 
vious works are scattered over a series extending to many years of 
English journals and other periodical works, they are not so easily or 
generally accessible as were to be desired, and accordingly several of the 
continental arachnologists seem not to be aware of them. We are therefore 
so much the more thankful for the work before us, which unites to a whole 
in an independent treatise and worthily completes the author’s previous 
labours in illustrating the spider-fauna of Great Britain and Ireland. 
As we have already seen (p. 25), this work contains descriptions 
of 304 species, distributed into the following 12 families: Mygalide (1 spe- 
cies) Lycoside (21), Salticidæ (18), Thomiside (29), Drasside (21), Cini- 
flonide (9), Agelenide (15), Theridüde (28), Linyphüde (116), Epeiride (32), 
JDysderide (7) och Scytodide (1). It is preceeded by an introduction, in 
which the author gives a short general account of the external and internal 
structure of the spiders, their economy, the construction of their webs and 
their manner of living, which is so much the more valuable, as being found- 
ed on BLACKWALL'S own observations and discoveries. This is perhaps 
the ground on which the respected author labours with most success: as a 
systematizer he does not appear to us to be always quite so fortunate. We 
cannot, for example, accept the authors method, proposed by him in 1841 ?), 
and since then constantly maintained, of dividing the spiders into 3 tribes 
distinguished by the number of the eyes: Octonoculine with 8, Senoculine 
1) BLACKWALL seems not to have witnessed a peculiarly important fact ascer- 
tained many years ago by MENGE (Ueb. die Lebensw. d. Arachn., p. 36), viz. that 
the male spider, before the act of copulation, emits from the sexual aperture situated 
under the base of the abdomen, a drop of sperma on a kind of small web made for 
the purpose, which drop he then takes up in the genital bulb of the palpi. This 
process has newly been observed also by AussERER (Beob. über die Lebensw. der 
Spinnen, pag. 194 et sequ.) 
2) BLAckw., The differ. in the numb. of eyes ete., p. 632. 
