650 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Kerguelen Islands. It differs from all known lice in a remarkable 

 character : the upper surface of the thorax and especially of the abdo- 

 men is covered with broad scales which closely resemble those of butter- 

 flies. This new form is nearest to Ecliinophfhirus from seals, e.g. 

 Phoca. 



Spermatogenesis of Blatta germanica.* — A. Wassilieff describes 

 the succession of changes manifested by the centrosome in the develop- 

 ment of the sperm-cell in Blatta. Briefly these are as follows : In the 

 spermatogonia they are " points " ; in spermocytes of the first order, 

 V-shaped ; in spermocytes of the second order, a pair of rods ; in 

 spermatids (a) a single rod ; in spermatids (b) two point-like bodies as 

 in the spermatogonia. 



Palaeoblattina Douvillei.f — M.Agnus adduces evidence to show 

 that this fossil, described by Brongniart in 1884 as the impress of an 

 insect wing, is to be referred to the Trilobites. As he shows from the 

 channelling and ornamentation upon it, Palceoblattina is a cheek-plate 

 of an Asaphus. 



5. Arachnida. 



North American Species of Limnesia.J — B. H. Wolcott gives a 

 diagnostic key to the North American species of this universally dis- 

 tributed water-mite. The list stands at nine species, the author having 

 added five, of which two are new. This mite may be recognised, in 

 general, by its oval, highly arched body ; by the presence of two eyes 

 on either side of the body anteriorly ; by the absence of claws on the 

 last pair of legs, which end in a sharply-pointed distal segment ; and 

 by the characters of the epimera and the genital area. The individuals 

 are active and brightly-coloured, of rather large size, and with pro- 

 nounced cannibalistic tendencies. 



Notostigmata : New Sub-order of Acari.§ — C. J. Witte describes 

 Eucarvs ( = Opilioacarus), a new type of mite which requires a new 

 sub-order to itself, and appears to be of great taxonomic interest. The 

 integument is relatively delicate, without sclerites. There is a large 

 segmented abdomen. A movable pseudocapitulum is defined off. The 

 labrum, divided into a basal clypeus and a distal labrum proper, is 

 united with the fused maxillre, and bears a pair of well-developed 

 maxillary (lateral) lobes. Two labial appendages ( = tritosternum) are 

 present. The trochanters of the third and fourth limbs are two-jointed. 

 There are numerous "lyriform fissures." Four dorsal stigmata occur 

 on the abdomen. The intestine opens by an anus. 



Hungarian Species of Eylais.|] — E. von Daday, who is preparing 

 a monograph on Hungarian Hydrachnida, discusses the genus Eylais. 

 He has found sixteen Hungarian species, five of them being new. 



* Zoo]. Anzeig., xxviii. (1904) pp. 257-60. 

 + Comptes Rendus, exxxviii. (1904) pp. 398-9. 

 J Trans. Amer. Micr. Soc, xxiv. (1903) pp. 139-60 (2 pis.). 

 § Vidensk. Medd. Nat. For. Kjobenbaven, 1904, pp. 137-92 (3 pis.). See Zool. 

 Centralbl. xi. (1904) pp. 511-24. 



il Math. Nat. Ber. UDgarn., xviii. (1903) pp. 340-64 (8 figs.). 



