174 SUMMARY OF CURRENT RESEARCHES RELATING TO 



disappear, probably with the aid of the leucocytes which subsequently 

 often show carmine corpuscles. The author describes the heart in detail. 



Food-Canal of Larvae of Cuckoo-Spit.* — G. O-add has studied the 

 structure of the gut in the larvae of Aphrophora spumaria. Besides the 

 Malpighian vessels (two pairs) which open into the intestine, there are 

 two long caecal appendages of the stomach. The first, which opens into 

 the anterior part of the stomach, has in its posterior half large cells 

 with spherules which give evidence of substances belonging to the 

 guanin group. The second appendage, which opens into the posterior 

 region of the stomach, has quite different cells with long processes. 

 The two are united terminally by connective tissue. The first is 

 excretory, the second glandular. Gadd points out that in Arachnoids 

 and Amphipods the mid-gut appendages have an excretory function. 



Normal Asymmetry of the Wings in Naucoris cimicoides.f— 



■Gunther Enderlein makes an interesting note on the fact that the 

 anterior right wing of this aquatic insect is different from the left. 

 The stigmata lie on the dorsal surface of the flat body and are covered 

 by the wings which leave a space between them and the back. This 

 space is an air-reservoir, and it requires to be tightly shut. In adapta- 

 tion to this end the right wing is strengthened and modified for effective 

 ■closure, and it is always on the top. In related forms, e.g. in the exotic 

 Macrocoris flavicollis from Zanzibar, the right wing is always uppermost. 

 This is a fine example of adaptation to a peculiar mode of life. 



Injurious Influence of Thrips on Man.| — S. Artault de Yevey de- 

 scribes an interesting case of a feverish tuberculous patient who suffered 

 from extreme itching on the uncovered parts of his body. These were 

 attributed by him and his nurses to small black insects which came in 

 crowds through the open window. The author identified them as 

 Melanothrips obesa Fr., which were attracted to the patient at his crises 

 of high temperature, and left him in the intervals. It is suggested that 

 the irritation was due to the minute insects introducing their probosces 

 into the sudoriferous pores. 



Statistical Study of Scale Insects on Fruit. § — L. Reh has made 

 a detailed study of the occurrence of various species found on fruit 

 brought to Hamburg, — species of Aspidiotus, Mytilaspis, and Chionaspis. 

 He gives statistics as to the occurrence of males, as to age, as to the 

 number of dead forms, as to distribution on the fruit, and as to the 

 spots caused by the parasites. 



His investigations lead him to the general conclusion that all morpho- 

 logical characteristics (individual, specific, and generic) are associated 

 with corresponding oecological or physiological peculiarities. 



Chemical Defence and Other Adaptations in North African 

 Orthoptera.|| — J. Yosseler discusses the defensive adaptations of Ortho- 

 ptera from the desert regions of North Africa, — where there is a high 



* Trav. Soo. Imp. Nat. St. Petersbourg, xxxii. (1902) pp. 65-95 (1 pi.). 



t Zool. Jahrb., xv. (1902) pp. 561-2 (3 figs.). 



t Bull. Soc. Zool. France, xxvii. (1902) pp. 207-9. 



§ Zool. Jahrb., xvii. (1903) pp. 237-84. 



II Verb. Deutsch. Zool. Ges. xii. Vers. (1902) pp. 10S-21 (4 figs.). 



