30 Arachn, 
ARACHNIDA. 
ment ; showing chiefly that the division of the dorsal plate is no criterion 
of species ; various species having this character in an immature stage. 
Its division is mostly a question of degree, and affords no sound basis for 
classification, as applied by Koch, Kramer, and other authors. The 
dorsal plates alter in size, shape, and development, when the Acarid 
changes its skin. Some conclusions of Megnin upon this subject, and 
also in respect to the conditions and mode of copulation are dissented 
from. The species noted are Gamasus coleoptratorum, Linn., and G. 
(^A earns) crassipes, Linn. ; both species are figured in various stages. 
Gamasus halleri, liter alls, falciger, mucronatus, pectinifer^ Icrameri, and 
hamatus, spp. nn., G. & K. Canestrini, Atti 1st. Venet. (5) vii. Venezia. 
G. tei'reus, sp. n., G. Canestrini & F. Fanzago, op. cit. iv. p. 116, Trentiuo, 
Veneto. 
Nicoletia, g. n. Cephalothorax furnished with four horns ; legs long 
and of uniform length. For N. cornuta, sp. n., Canestrini & Fanzago, 
Atti 1st. Venet. (5) iv. p. 120, pi. iv. fig. 2, Trentino. 
Dermanyssus sylviariurn^ p. 124, parasitic on Sylvia atricajnlla, and 
D. richiardii, p. 125, on Xylocopa violacea and Cossus liyniperda, 
spp. nu., iid. 1. c. 
Notaspis tridentinus^ sp. n., iid. 1. c. p. 126, Trentiuo. 
Uropoda.^ De Geer. The Swiss species of this genus (6 in number, all 
known), are described by G. Haller, Arch. f. Nat. 1881, pp. 182-187, 
pi. ix. figs. 1-6. 
Epicrius^ Canestr. & Fanz. The Swiss species of this genus (3 in num- 
ber, all known), are described ; Haller, 1. c. pp. 188-190, pi. ix. figs. 7-9. 
Gg. Seius and Zercon compared with Gamasus ; Kramer, Z. ges. Naturw. 
liv. pp. 429-433, pi. iii. fig. 8. 
IxODiDiE. 
G. Haller, Zool. Anz. iv. pp. 165-167, with woodcuts, describes the 
organ of hearing in a species of Ixodes. This organ is on the first pair 
of legs. 
P. Bertkau, SB. niederrhein. Ges. xxxviii. pp. 145-148, treats upon 
the propagation of Ixodes ricinus, and comes to a different conclusion, 
on the feeding of the adult male, from M6gnin (C. R. Ixxxiii. p. 993). 
On the copulation of this species the views of De Geer, Von Siebold, 
Pagenstecher, and M(5gnin, are discussed. The mode of transferring the 
spermatozoa appears doubtful. The differences between the spermatozoa 
in the testes and those in the receptaculum seminis are pointed out. The 
placing of the eggs in the bladder is described, and the function of this 
latter organ is conjectured to be the protection of the eggs from dessication. 
Ixodes punctulatus, sp. n., Canestrini & Fanzago, Z. c. p. 183, Italy, on 
Cervus capreolus. 
Ilyalomma dentatum, sp. n., Canestrini & Fanzago, 1. c. p. .186, Pisa. 
Ilcema\to'\i)hysalis sulcata., p. 188, on Lacerta viridis ; H. punctata, 
on Dama vulgaris, and II. rhinoloplii, on Rhinolophus ferrum-equinum, 
p. 189, spp. nn., iid. 1. c. 
RMpidocephalus bursa, sp. n., iid. 1. c. p. 190, on the wild boar. 
