ZOOLOGY AND BOTANY, MICKOSCOPY, ETC. 183 



great increase in the size of the cell. The pathway taken by the itomore 

 through the cytoplasm persists and grows stronger ; by a condensation 

 of the cytoplasmic reticulum in this pathway the axial filament of the 

 spermatozoon is formed. The author regards the accessory chromosome 

 as a reservoir in which is deposited the nuclear chromatin. 



5. Arachnida. 



New Genera of Hydrachnids.* — Sig. Thor describes as Hjartdalia 

 uncinata g. et sp. n., and Mesobates forcipates g. et sp. n., two new forms 

 obtained in Norway. The first named genus is nearest to Aturus Kramer, 

 but the genital cups are numerous, small, and extend in a broad band at 

 either side from the extremity of the ventral surface forwards towards 

 the insertion of the last pair of legs. In a note on two specimens of 

 the new species observed in copula, the author gives reasons for sup- 

 posing that the fourth pair of legs act as carriers of the spermatozoa. 

 The genus Mesobates occupies an intermediate position between Megapus 

 and Hygrobates ; as regards the maxillae it is nearest the latter genus, as 

 regards other structures the former. The paper includes descriptions 

 of two other new species. 



New Hydrachnids. — A. Protz t describes as Aturus crassipalpis 

 sp. n. a new species of Hydrachnid found in a collection from Switzer- 

 land. Swimming bristles are absent from the legs, and on the fifth joint 

 of the fourth pair there is a hollow from which springs a sabre-shaped 

 bristle. 



E. Piersig J describes as Aturus protzi a new species which, though 

 closely related to A. intermedius, from the nature of the bristles on the 

 fourth pair of legs merits specific distinction. It was taken in the 

 Bohemian- Bavarian forests, and the female is unknown. 



From the same district Piersig § describes as Aturellm crassipalpis 

 g. et sp. n. another new form, which, as regards the structure of the 

 fourth pair of legs, seems at least in part to resemble Protz's Aturus 

 crassipalpis. 



South American Acarids.|| — A. Berlese and G. Leonardi describo a 

 collection of Acarids made by Dr. Silvestri Filippo, many of which 

 prove to be new species, some falling into new genera. The new genera 

 are Celsenogamasus, which is closely related to Gyrtolaelaps ; Urozercon, 

 with one species from termites' nests ; and Stereotydeus, which is closely 

 related to the genera Ereynites and Penthaleus. 



Myrmecophilous Mites. ^[ — E. Wasmann, in an interesting paper on 

 this subject, points out that some confusion has hitherto existed in 

 regard to the European species of Antennophorus. He distinguishes the 

 following three species : — A. uhlmanni Hall, parasitic on Lasius fuligi- 

 nosus, L. mixtus and L. umbratus, A. pubescens Wasm., on L. fiavus, and 

 A. foreli sp. n., on L. niger and L. alienus. According to his observa- 

 tions each worker, save in exceptional circumstances, does not bear more 



* Zool. Anzeig., xxiv. (1901) pp. 673-80 (13 figs.). 



t Op. cit, xxv. (1901) pp. 1-2 (2 tigs.). \ Tom. cit., pp. 33-5 (1 fig.). 



§ Tom. cit., pp. 18-20 (3 figs.). || Tom. cit.., pp. 12-6. 



U Tom. cit., pp. 66-76. 



