52 Aiachn. 
AKACHNIDA. 
Ophiocoma erinaceus^ Bohm, MB. Ak. Berl. 1879, pp. 177-183, pi. i. fig. 4, 
and pi. ii. fig. 1. P. breviceps, sp. n. (with small palpi in the male), id. 
SB. nat. Fr. 1879, pp. 54, 69 & 60, Japan. 
Phoxichilidium {Anoplodactylus) digitatum^ sp. n., id. MB. Ak. Berl. 
1879, p. 184, pi. ii. fig. 2, Singapore. 
Phoxichilus meridionalis, sp. n., id. 1. c. p. 189, pi. ii. fig. 4, Singapore. 
Pycnogonurn Utorale (Strom.), specimen from Kerguelen Island with 
scarcely pointed rostrum and two small knobs behind the eyes, and P. (?) 
chelatum, sp. n., perhaps the young state of a species nearly allied to P. 
Utorale, locality unknown ; id. 1. c. pp. 191-194, the latter pi. ii. fig. 5. 
Pycnogonurn, Utorale var. n. tenue, South-west Japan; Slater, Ann. 
N.H. (5) iii. p.283. 
ACARIDEA. 
Michael, A. D. On some peculiarities in the reproductive system of 
certain of the Acarina. J. Quek. Club, 1879, pp. 22.3-230, pi. xiii. 
Deals with the mode and period of fertilization in the Dermalichi, 
and describes and figures what the author consideis to be the female 
external sexual organ in Glyciphagus, in which he differs from previous 
writers ; describes the dorsal position of the male organ in Myobia, &c., 
and details the structure of the oviduct in the Oribatidce, and the means 
by which its great expansiveness is obtained. 
OEIBATlDiE. 
Michael, A. D., & George, C. F. A Contribution to the Knowledge of 
British Oribatidce. J. R. Micr. Soc. ii. pp. 225-251, pis. ix.- xi. 
This paper, apparently the first systematic attempt to deal with the 
subject in this country, gives the distinctive characters of the family and 
refers to the principal bibliography. In addition to the new genus and 
3 new species recorded infra, 41 species of this family are noticed (nearly 
all for the first time) as belonging to the British fauna, viz. ; — Pelops 1, 
Oribata 9, Lyosoma 4, Cepheus 2, Notaspis 4, Eremceus 2, Nothrus 6, 
Damceus 6, Tegeocranus 2, Hermannia 2, and Hoplophora 3. 
The various contrivances are detailed by which the legs are protected 
when these mites, which are without defensive weapons, simulate death, 
and other protective provisions for the safety of various species are 
noticed, also their habitats (chiefly moss, fungi growing on trees, decay- 
ing wood, &c.). The transformations of several species are described ; 
also the mode of escape of the larva from the egg in Damceus geniculatus 
and D. clavlpes ; the change from nymph to perfect creature in Tegeo- 
cranus latus, Oribata punctata, &c., and the very remarkable nymph of the 
former, previously unknown, is described and figured, with the mode in 
which the skin was cast. All transformations described are from actual 
observation of the various stages. The conclusion is arrived at, from expe- 
riment, that these mites, which are without apparent eyes, have some 
limited vision, and it is contended that what have been known as the 
protecting hairs of the stigmata are really sense organs. 
