424 SUMMARY OF CURRENT RESEARCHES RELATING TO 



^muscle-insertion. In Peripatus the tracheal pouches are numerous in 

 each segment, and do not serve for muscle-insertion. Perhaps those 

 of Diplopoda correspond to enlarged tracheal pouches of Onychophora. 



2. The tracheal pouches of Peripatus have a fine cuticle ; those of 

 Diplopoda have a strong chitinous layer, but this difference is of 

 rsubordinate importance, being correlated with the difference in the 

 general cuticle of the body. 



o. The trachea of Peripatus have a great resemblance to the fine 

 trachea3 of Diplopoda. 



Tracheae in Polydesmus.* — W. Effenberger describes the tracheal 

 system of this Millipede. In each ordinary segment there are in close 

 relations to the limbs four tracheal or stigmatic pouches of complex 

 form. From these there arise the tracheae, which are all of one kind, 

 namely, fine tracheae, of very narrow lumen, without observable spiral 

 thread, and never branching or uniting with others. A sketch of their 

 general distribution is given. The supply of the anterior region is dis- 

 cussed more particularly. 



S. Arachnida. 



Structure of Spiders' Eyes.f — E. Widmann has studied the minute 

 structure of the eyes in species of Epeira, ZiUa, Meta, Tegeneraria, 

 Theridium, Amaurohius, and Lycosa. He describes (A) the " inverted " 

 type seen in the two anterior median eyes (" main eyes " of other 

 investigators) where the rods lie in front of the entrance of the nerve, 

 and (B) the " vertierte " type, seen in the other six (or 4) eyes (" acces- 

 sory eyes " of other investigators) which arise as simple invaginations of 

 the ectoderm. He distinguishes three groups of B, according to the 

 nature of the tapetum. 



Note on Spelseorhynchus prascursor Nn.| — L. G. Neumann calls 

 attention to the fact that this Acarid which he described provisionally 

 as a parasite of the ox, from Africa, was associated in error with 

 Hyalomma (Bgyptium. It appears that Spelchorhynchus is a parasite of 

 bats, and that tropical America, not Africa, is the locality to which it 

 should be referred. 



e- Crustacea. 



Regeneration of Caudal Filaments of Apus cancriformis. § — 

 0. Rabes has observed clear and perfect regeneration in this case. After 

 three moults the animal was superficially normal. The mutilation was 

 effected on October 22 : the restitution was complete on November 26. 



Nephro-phagocytes of Crustacea. || — L. Bn^ntz describes these in 

 Decapods and Stomatopods. They have already been noted in Isopods, 

 Amphipods, Leptostraca, and Schizopods. They are cells which are at 

 once excretory and phagocytic ; they have been observed taking in 

 soHd particles at the same time as they are eliminating injected coloured 



* Zool. Anzeig., xxxi. (1907) pp. 782-6 (4 figs.). 



t Tom. cit., pp. 755 62 (7 figs.). J Arch, de Parasitol, x. (1906) p. 220. 



§ Zool. Anzeig., xxxi. (1907) pp. 753-5 (4 figs.). 



\\ C.R. Soa Biol. Paris, Ixii. (1907) pp. 423-5. 



