ARACHNIDA. 
143 
Thomas, Friedrich. Ueber Phytoptus, Duj., iind eine grossere 
An.zahl neiier odcr wenig gekarmter Missbildungen, welche 
diese Milben an Pflanzen hcrvorbringen. Zeitschr. ges. 
Naturwiss. Band xxxiii. pp. 313-366, plate 4. 
Tiiorell, T. On European Spiders. Part I. Review of the 
European Genera of Spiders, preceded by some observations 
on Zoological Nomenclature. Nova Acta Regiie Soc. Sci. 
Upsal. scr. 3. vol. vii. pp. 1-242 (November 13, 1869, pp. 1- 
108, and February 16, 1870). Also published separately 
under the above title. 
This is undoubtedly the most valuable contribution to the 
knowledge of the Araneida that has appeared of late years. The 
author discusses in it the general classification of the group, and 
the bibliography and literature of the subject generally ; and 
many remarks upon extra-European forms of Spiders will be 
found scattered through it, or in the notes appended to the text. 
The author has also discussed the general question of zoological 
nomenclature and synonymy, his remarks upon which are exceed- 
ingly valuable. A great number of generic names are changed 
by the author on account of their having been preoccupied in 
other groups (see especially p. 37). Thorell also gives a notice 
of Fossil Spiders, including descriptions of some new forms. 
Wood, H. C. On the Phalangese of the United States of Ame- 
rica. Communications of the Essex Institute, vol. vi. 
pp. 10-40 (1868). 
. On the Phalangia and Pedipalpi collected by Professor 
Orton in Western South America, with the description of 
new African species. Trans. Amer. Phil. Soc. n. s. vol. xiii. 
pp. 435-442, plate 24. 
ARANEIDA. 
Thorell (European Spiders, part I.) proposes to divide this 
order (which he calls Arane<e) into 7 suborders, nearly corre- 
sponding to the families of Latreille, namely the Orbitelai'icB, 
Retitelarice { — InmquitelcR, Lat.), Tubitelari<B, Territelarics ^ Citi- 
grad(R, LaterigradcR^ and Saltigrad(S, These include in all 22 
families (16 of which are represented in Europe), of which the 
author gives a scheme or diagram showing their mutual relations 
in accordance with the hypothesis of evolution — that is to say, 
on the principle of propinquity of descent,^^ which he regards, 
with Darwin, as the sole cause of the similarity of organic beings. 
This diagram we cannot reproduce here ; but its general indi- 
cations may be understood from the following statement. The 
whole genealogical tree of the true Spiders springs from the 
Opiliones) it forms two branches, one of which is simple, the 
M 2 
