Appendix Entomology of the Rose. 371 



and is commonly known as the Cuckoo Spit. It may often be observed on the under side 

 of Rose leaves or on the young twigs. The larva which this froth serves to conceal varies 

 in colour from green to pale yellow. If eliminated from its protecting element it immedi- 

 ately sets to work and manufactures a fresh supply, and in a short time is again safely 

 hid from view. The perfect insect is about a third of an inch long, brown in colour, some- 

 times a little greenish. Its head, thorax, and wing cases are finely punctured, and on the 

 latter are two white spots ; its underside is pale brown. The injury it does to Roses seems 

 confined to the larva state, when it preys upon the sap. 



The other variety of Cicada (C. rosce) is much smaller than the last named. In length 

 it is about one and a quarter line. Its usual colour is pale yellow, but it inclines sometimes 

 to green, at others to nearly white ; it is, however, always of one colour, never spotted. 

 It is elongated in form and cylindrical, a feature it owes to the wing cases, which are 

 folded and envelope the body. We have often observed this insect late in the autumn on 

 standard Rose-trees, from which, when shaken, numbers would rise into the air leaping 

 and flying. We must confess our ignorance of the economy of this species, but Guillemeau, 

 a French author, states that the eggs are laid upon the Rose, and the larva probably feeds 

 on the sap. 



Thrip (Thrips h&morrhoidalis) is also sometimes found on Roses under glass. This insect is 

 very destructive ; two or three will devour the under side of a leaf in the course of one night. 

 Their presence may be detected by the yellow appearance of the upper side of the leaf, which 

 when examined will show the under side eaten. The best means to adopt for the extermination 

 of this insect is a solution of soft soap, either dipping the affected shoots in it or syringing 

 freely. It rarely appears, however, on clean and healthy plants. Out-of-doors in hot dry 

 summers it is often very destructive to Rose flowers, especially white and pale coloured 

 blossoms, which'.it greatly disfigures with numerous small punctures, giving them a dirty and 

 spotted appearance. 



In the natural order ARACHNIDS, which includes spiders and mites, and the family Aearidce, 

 we have the Red Spider (Acarus tellarius), so well known to most cultivators of greenhouse 

 plants, and which is often to be found on Roses under glass, especially during the late summer 

 months. It is very minute, and, as its name implies, is red in colour. It proves injurious to 

 the plants by settling on the leaves and abstracting the sap. It is generally found on plants 

 which have been kept too dry, and a moister atmosphere will almost certainly ensure its 

 disappearance. 



This closes our list of injurious insects, and while on the one hand we do not think that 

 many species which may be regarded as generally noxious are absent from this enumeration, on 

 the other we hope that the accounts and details here furnished will not be found to be 

 exaggerated. There remains, however, a pleasing duty to perform, with which these remarks 

 will be closed, and that is a few words on the useful insects of the Rose. The Rose belongs to 

 the Linnsean class, Icosandria polygynia ; it has not therefore the need of the agency of the 

 insect world to the perfection of its seed that monsecious and disecious plants have ; but there is 

 no doubt but that bees and others materially assist the operations of nature in this respect. 

 There are, however, a few species which are designed to keep in check the ravages of others, 

 and it is to them we specially refer. None perhaps answer to this end to a greater extent than 

 the Ichneumon flies (Ichneumonidce) and their allies the Chalcididce. Both these classes belong 

 to the order HYMENOPTEBA ; we therefore see that although this order embraces some of the 

 most mischievous insects, it nevertheless furnishes us to a certain extent with an antidote. The 

 species of Ichneumon flies merge so gradually into one another that classification without the 

 aid of a microscope is impossible. Their bodies are for the most part black and shining, and 

 their wings transparent. Their number is so great that nearly every kind of caterpillar has its 



