184 SUMMARY OF CURRENT RESEARCHES RELATING TO 



than one parasite, this almost invariably occurring in one definite 

 position on the under side of the head of the host. Here it is able to 

 exert such pressure on the crop of the host as to cause the latter to 

 regurgitate food-material which is eagerly licked up. In the feeding of 

 one worker by another also, the parasite comes in for its share ; but 

 there is no direct connection between parasite and host. Parasitised 

 ants are very shy, concealing themselves more quickly than others if 

 the nest be exposed, and frequently exhibit an uncertainty of gait. The 

 author describes in detail the observations which lead him to the con- 

 clusion that the mites are not guests, but are what he describes as 

 parasitic caricatures of guests. His experiments show that transference 

 from one nest to another of the parasite is possible if the inmates of 

 the strange nest be suitable hosts. An interesting experiment was the 

 placing of an infected specimen of Lasius fiavus in a Formica sanguinea 

 nest ; the Lasius was bitten to death, and its parasite climbed on the 

 body of one of the attacking forms, but it was unable to obtain a hold 

 here, the larger and stronger Formica being able to remove the small 

 parasite by means of its fore-legs, an operation which the species of 

 Lasius attempt, but are unable to carry out. 



The paper also contains an account of the two known American 

 species of Antennophorus, and of some related European myrmecophilous 

 mites belonging to other genera. Further, the author points out that 

 the resemblance as regards mode of life between ants and termites, is 

 emphasised by the similarity of their guests and parasites. Into so 

 much detail is this carried, that there have been described from the 

 nests of termites, mites which in all probability belong to the genus 

 Antennophorus. 



Breathing Organs of Pseudoscorpionidae.* — J. P. Stschelkanovzeff 

 has made some observations upon these organs in two species of Chernes. 

 He finds that the stigmata resemble those of insects in having a frame 

 of thickened chitin round their margin. The outer opening does not 

 lead directly into the trachea? but into a stigma-chamber, in whose 

 walls lies the opening into the tracheal stem. The closure of the stig- 

 mata is provided for by a mechanism consisting of a chitinous thickening 

 of the wall of the chamber, and of two muscles, one of which opens and 

 the other closes. In general type therefore, the closing mechanism 

 resembles that of insects. The main tracheal stems do not possess a 

 spiral thread, and in general structure, position, and significance recall 

 the initial tracheae (trochees d'origine of Strauss-Durckheim) in insects, 

 and the stigmatic pockets of the trachea? in Diplopoda. The fasciculi 

 of fine trachea? do not arise from the summit of the main stem, but from 

 the anterior end of its inner wall, so that all the little tubes of the fasci- 

 culus are united at one spot of the wall, as also occurs in Diplopoda. 

 At this spot the whole of the inner wall is covered by folds ot chitin, 

 which prevent the entrance of foreign bodies into the fine tracheal tubes. 



Arctic Pantopoda. f — G. H. Carpenter reports on the Pantopoda 

 dredged by W. S. Bruce in 1898 in the Arctic Ocean. The eight species 

 recorded are all fully described and figured in Sars 1 monograph (1891). 



* Zool. Anzeig., xxv. (1902) pp. 126-35 (5 figs.), 

 t Sci. Proc. E. Dublin Soc, x. (1900) pp. 279-82. 



