"34 N. S. ENTOMOLOGICAL SOCIETY. 



NOTES OF TWO SPECIES OF TREE-HOPPERS Membracldae 

 OVIPOSITING IN THE APPLE. 



,By W. H. Brittain. 



SEVERAL species of tree-hoppers oviposit in apple buds and bark, but only the 

 two herein described are at all common, and only one is of any great economic 

 importance. The following notes represent the observations made during the 

 summer of 1916. 



CERESA TAURINA FITCH. 



In the spring of 1915, while watching some pear twigs for the emergence of the 

 green apple bug (Lygus communis var. novascotiensis Knight), a number of t'ny Mem- 

 bracid nymphs were noticed feeding upon the petioles of the unfolding leaves. Further 

 «x mination showed the empty egg shells of the insects and numerous unhatched eggs 

 inserted in the buds. An attempt was then made to rear these nymphs on apple and 

 pear seedlings in the insectary, but though some of them reached the last nymphal stage 

 they all died before attaining maturity. 



The following spring a number of twigs bearing infested buds were collected and 

 placed in water in the laboratory. The various grasses and weeds found growing in the 

 orchard were planted separately in flower pots and also crowded together in a number 

 of boxes, and on these plants the nymphs were placed as they emerged. Though the 

 nymphs will apparently feed upon a number of plants, provided the growth is suffici- 

 ently succulent, they did not feed readily upon any of the plants gathered, with the 

 exception of the Sheep Sorrel (Rumex acetoseVa). In the orchard, also, by far the larg- 

 est number of nymphs were found feeding upon this plant, though they were noticed 

 in a thriving condition on blackberries and a few scattering specimens were found 

 upon other plants. 



In feeding the nymphs, select the tender succulent growth that develops under 

 conditions of heavy shade. They could be found feeding in large numbers on the plants 

 growing among a heavy stand of grass and clover, but would not feed upon the tougher 

 growing plants in isolated situations, where they would be exposed to light. They can 

 be carried on for a considerable length of time upon succulent pear twigs, feeding on the 

 tender shoots or leaf petioles, girdling them. We have not succeeded, however, in rear- 

 ing them to maturity upon the pear. 



The adults e'use to feed upon the plants that sustained the nymphs. Th^y evid- 

 ently maintain themselves upon succulent pear and apple twigs during the breeding 

 and oviposition period. 



NATURE OF INJURIES. 



Owing to the large number of incisions made in a single limb it would naturally be 

 expected that the new growth would be injuriously affected. In some cases as many as 

 13 may be laid in a single bud, forming a complete girdle around it. We have never 

 been able, however, to detect the slightest injury to the buds, even in extreme cases. 



DESCRIPTION OF THE INSECT. 



The adult insect is a peculiar triangular creature, with the front angles of the pro- 

 thorax produced into lateral horn-like projections. The nymphs present even a more 

 peculiar appearance. They are triangular in shape and their dorsal surface is beset with 

 strong spines. They are green in color. 



