Insecta. 97 



The butterflies known from this area are then dealt with in systematic 

 Order, local distribution etc. being discussed under each one, and the general 

 distribution being also given. After this the author gives certain interesting con- 

 clusions. The butterfly fauna of this area is a very poor one, and has a di- 

 stinctly desert character. Several groups are very poorly represented, both in 

 species and individuals, notably the Satyrinae and Acraeinae: the Papilio- 

 ninae, Nymphalinae, and Danainae are also few: the Lycaenidae are more 

 numerous in species, but mostly inconspicuous. The most abundant group is the 

 Pierinae, which contribute 33 species, among which the genus Teracolus is do- 

 minant, some of its species occurring also in very great numbers. 



Comparing the White Nile Fauna v^^ith that of Southern Arabia (mainly 

 known from the district near Aden), it is seen that the latter has an even poorer 

 fauna. The most striking difference between it and that of the White Nile, is 

 that the group Acraeinae is entirely wanting in Southern Arabia. Otherwise 

 the distribution of species among the families is very similar. 75 species are 

 known from the White Nile and 50 from S. Arabia, and 38 of these are com- 

 mon to the two faunas. The comparison is elaborated by means of tables. 



H. Scott (Cambridge). 



237) Chapman, T. A., Pupal moult oi Ägriades coridon; the maxillary 

 pocket of Plebeiid pupae. In: Ent. Record and Journ. Variation, Bd. 25, 

 Heft 6, Taf. 11, 12, S. 165—6, 1913. 



In the pupa of this butterfly the extremities of the maxillae are enclosed 

 in a pocket, which projects into the interior of the pupa between the 4* ' and ö'*^ 

 abdominal Segments. It is not visible from outside, being hidden by the extre- 

 mities of the wings and antennae. The author observed the actual formation of 

 this pocket. When the last larval skin is moulted, the intersegmental membrane 

 between segments 4 and 5 is stretched to its füllest width and the extremities 

 of the maxillae reach to the middle of it. By the movements of the segments 

 during the moult, the intersegmental membrane is repeatedly folded up (^each 

 time segments 4 and 5 come together) and stretched out again, and every time 

 it is folded up the extremities of the maxillae are enclosed between its folds. 

 When the segments finally close up together permanently, the extremities of the 

 maxillae are left permanently enclosed in the folds of the membrane, which con- 

 tracts round them and so forms the maxillary pocket. H. Scott (Cambridge). 



238) Eltringliaiu, H., On the scent apparatus in the male of Amauris 

 niavius Linn. In: Trans. Ent. Soc. London, Heft 2, S. 399—406, Taf. 20,1913. 



In 1877 Fritz Müller described the pockets lined with special scales in 

 the hind-wings of the JcT of two species of Danais, and also the extrusible brushes 

 of hairs situated in the anal region of these species. He suggested that the butter- 

 flies perhaps insert the brushes into the pockets, and so impregnate the brushes 

 with the scent produced in the pockets. This action has now been actually ob- 

 served in two species of the allied genus Amauris; and the author of the present 

 paper describes minutely the structures concerned, as found in one of the two 

 species in question. 



In Amauris niavius c? the hind-wings do not bear pockets, but specialised 

 scent-producing patches. On the upper surface of these patches are a number 

 of raised oval areas each with a rainute central pore: under each of these areas 

 is a mass of glandulär tissue, producing the scent. Alternating with these oval 

 areas are scale-sockets bearing covering scales. In the species of Danais studied 



Zentralblatt f. Zoologie, allgom. n. experim. Biologie. Bd. 4. 7 



