332 



Bagnall (R. S.)- On Two Species of Physothrips (Thysanoptera) 

 injurious to Tea in India. — Bull. Entom. Research, London, ix, 

 part 1, May 1918, pp. 61-64, 2 figs. 



The author describes Physothrips setiventris, sp. n., and P. lefroyi, 

 Bagn., both of which have been found on tea in India in sufficient 

 numbers to be regarded as pests. 



Bagnall (R, S.). On the Rubber Thrips {Physothrips funtumiae, Bagn.) 

 and its Allies. — Bull. Entom. Research, London, ix. part 1, May 

 1918, pp. 65-70, 3 figs. 



Three species belonging to the genus Physothrips are described in 

 this paper with a key to the characters of each sex. These are : — 

 P. marshalli, sp. n., from the Gold Coast, found in the flowers of a 

 variety of plants : Physothrips funtumiae, Bagn. (rubber thrips) from 

 Uganda and Southern Nigeria ; and ^ P. kellyanus, Bagn. , from 

 Queensland and Victoria. 



Distant (W. L.). Descriptions of some Capsidae from the Belgian 

 Congo. — Bull. Entom. Research, London, ix, part 1, May 1918, 

 pp. 71-73, 3 figs. 



The following Capsids are described : Lycidocoris mimeticus. Rent. 

 & Popp., found on coffee bushes and also occurring in Uganda ; 

 X. modestus, sp. n., on cinchona ; L. thoracicus, sp. n. ; Chamus 

 bellus, sp. n. ; C. tuberculatus, sp. n., on guava. 



Tragi ARDH (I.). On a New Method of ascertaining the Parasites of 

 the respective Host-Insects in a Mixed Infestation.~£wZ^. Entom. 

 Research, London, ix, part 1, May 1918, pp. 75-79, 5 figs. 



This paper elucidates a method of determining the position of the 

 parasites of the various hosts that constitute the often comphcated 

 fauna of such material as the cones of coniferous trees, where each 

 cone usually contains two or three different injurious species. 



The cones were kept in breeding-cages and the insects emerging 

 from them were collected daily. Diagrams were then made illustra- 

 ting the percentage of each species that emerged during each day. 

 It was assumed that a certain relation existed between the time of 

 emergence of the host and its parasite, the latter being adapted both 

 morphologically and biologically to its host and appearing invariably 

 at the moment most suitable for its successful propagation. 



Certain data already existed as to the relation of Nemeritis crema- 

 stoides, Hlmg., Ephialtes glabratus, Ratz., and Bracon sp. to Cydia 

 {Laspeyresia) strobilella, L. [see this Review, Ser. A, vi, p. 90]. It 

 was presumed that if other parasitic species grouped themselves round 

 one or other of the phytophagous species in a similar manner to 

 these species about their host, it might safely be concluded that they 

 were parasitic upon them. Fortunately the various phytophagous 

 species did not appear contemporaneously, but in a certain succession, 

 so that it was possible to ascertain the grouping of the parasites 

 around their hosts. Diagrams illustrating the curves of emergence 

 of the various species demonstrate the relations between host and 



