226 THE ENTOMOLOGIST. 



of " Cicadiiia " alone to be recorded from the British Isles, and 

 the total is quite likely to reach 325 or 330. As rich localities 

 practically unworked, I would specially recommend the Trossachs 

 and surrounding country in Scotland, but there is scarcely a 

 county more than very partially worked at. 



(b) Species already known. — The locality records in Edwards's 

 work are usually most meagre, which is, of course, not the 

 author's fault but due to the fact that workers are so few. 



(c) Food-plants. — This is a part of the investigation that 

 requires great care. It is obvious that a plant may be quite an 

 accidental resort of a leaf-hopper. For instance, Platymetopms 

 nndata has been recorded from Pteris aquilina and from Qnercus 

 robiir. Now, of course, it is possible that both records are correct, 

 but it is very doubtful. Platijmetopius iindata is so characteristic 

 that there is no chance of wrong identification of the species. 

 The probability, as it is a well-known fern-feeder, is that it was 

 taken from an oak tree surrounded by fern, the hopper having 

 jumped from the latter to the former, perhaps on the approach 

 of the collector. Though it is well, therefore, to record all plants 

 from which the adults are captured, it is necessary to note 

 specially those in which the eggs are deposited, or upon which 

 the nymphs are found. 



(d) Life-histories. — The eggs of nearly all the British forms 

 are probably inserted in slits made by the female in leaves, twigs, 

 or stems of plants, the exceptions being Issiis coleoptrata, which 

 probably lays them on leaves, &c., covering them with tlocculent 

 matter, and Tetigometra impressopunctata, which lives in ants' 

 nests, often under stones, and apparently drops its eggs in the 

 nest. Oliarus and Cixius probably lay their eggs under the 

 loose bark of trees. 



The nymphs are more or less like the adult in their four or 

 five instars, the rudiments of the flight-organs becoming more 

 and more apparent in each further stage. The tarsi are not 

 jointed, and there are other differences, while the nymphs are 

 often coloured quite differently from the adult. In theFulgoroid 

 families there are a number of remarkable sensory organs on 

 the head, thorax, tegminal and alar pads, and abdomen. 



The nymphs are usually easily reared, in most cases test- 

 tubes of medium size being all that is necessary. The several 

 stages should be described, the points to look for being : — (1) the 

 form of the head, which may differ from that of the adult, and, 

 indeed, in the various nymphal instars ; (2) the pattern and 

 colour ; (3) the number, colour, and disposition of the bristly 

 hairs on the abdomen. This last character has not been used 

 yet, but is of the greatest importance. 



(e) Parasites. — Leaf-hoppers are particularly subject to para- 

 sites, which are usually easily reared from them. The ova in 

 grasses and elsewhere will yield Chalcid, Eulophid, and Mymarid 



