HEMIPTERA 329 



Family Aphid^ 



Aphis brassicce, Linn. Cabbage Aphis 



This pest seems to have appeared at an early date after settlement. 

 It was very abundant 50 years ago, and is particularly common in 

 those districts of New Zealand where the annual rainfall does not 

 exceed 35 inches. It attacks every species of Brassica (cabbage, 

 turnip, swede, rape, etc.), and is found on many other crucifers 

 (Capsella, Sisymbrium, Cakile, etc.). Dr Hilgendorf considers that 

 it is the most destructive insect that has been introduced into the 

 country, and estimates that the annual loss due to its presence 

 cannot be put down at less than ,£250,000 ; and this not so much by 

 the direct damage it does, as the restriction it entails in the selection 

 of varieties which while more or less blight-proof, are not nearly as 

 productive as others^. 



Aphis persicce niger, Smith. Black Peach Aphis 



Mr D. Miller informed me that this insect, which appears to be 

 common in parts of Australia, has recently (1917) been recorded 

 from New Zealand (locality?). 



Chermes corticalis, Kaltenbach 



This species is recorded by Captain Hutton in the Index (1903). 

 None of my correspondents know it. 



Chermes pini, Koch 



In 1884 Mr Maskell recorded that pine trees were badly attacked 

 by a "blight" some four or five years previously. The species which 

 suffered were Pinus halepensis, P. radiata (P. insignis), and P. sylvestris. 

 The latter species was especially damaged in Nelson, while the former 

 about Wellington were greatly infested. It was also destructive in 

 plantations at Wanganui, Christchurch, Ashburton and Peel Forest. 

 The pest seems to be fairly common, and though it does not kill 

 pine trees, it disfigures them and greatly interferes with their vigorous 

 growth. Mr Maskell suggested that perhaps C. pini and C. corticalis 

 were the same species. 



Chermes laricis, Hartig. The Pine White Aphis 

 In the report on State Afforestation for 1901-11, this species is 

 stated by Mr A. H. Cockayne to be fairly abundant on some of the 

 pines, "but it appears to select trees that are of weak constitution, 



^ In the report of the Agricultural Department for 1905, two species are 

 recorded which, in the absence of certain literature, I cannot identify. They are: 

 (i) the turnip fly (Aphis rosce), which is recorded from Kohinui, and (2) the green fly 

 {Rophalosiphon dianthi), which is said to have been found on diseased tomatoes from 

 Wellington. 



