A GUIDE TO THE STUDY OF BRITISH WATERBUGS. 179 



Leven to the Shetlands. Collectors, especially those residing in 

 North and West Scotland, in West Ireland, and in Wales, will 

 do well to study the waterbugs of their neighbourhood, as no 

 doubt such examination will extend our knowledge of the distri- 

 bution of a number of rare species, and add new species to our 

 fauna, and possibly to science. 



One great advantage which the student of aquatic Khynchota 

 possesses over collectors of (for example) Lepidoptera is that 

 weather should make little difference to him. Should he be so 

 minded, he may sally forth during pouring showers or on a dull 

 cloud-obscured day, and find little or no diminution in the 

 number and quality of his captures. Collecting may be done, 

 moreover, all the year round. Hydronietridae appear to hyber- 

 nate in the perfect state ; the imagines being found from August 

 to June, the larvae from about May to August. Micronecta 

 hybernates in the larval state (according to Buchanan White), 

 but I have never found it then. All the other waterbugs passing 

 the winter fully developed, they may be looked for in the latter 

 state from about the end of July to the beginning of June, or 

 even, later. The ova are deposited in April or May, as a rule, 

 and the various larval stages are passed through from May to 

 the end of July ; but all these dates overlap and vary consider- 

 ably from year to year. April, May, August, and September 

 are perhaps the most productive and the most pleasant months 

 in which to collect, although certain species are more abundant 

 in the earlier months of the year. Notoneeta, Corixa, &c, may 

 be seen during the winter frozen and huddled together in masses 

 under the ice ; whilst Hydronietridae pass the same season under 

 moss or stones, often some distance from water. Waterbugs are 

 by no means of a solitary disposition (except perhaps the Nepidae) , 

 but usually occur together in some numbers, — several species of 

 Corixa appearing to move in small shoals ; so that when the 

 collector finds, either at the collecting-place or during a more 

 careful examination subsequently, that he has chanced upon a 

 rare or local species, he may work the same locality again, with 

 very good hopes of success. 



With the exception of the Nepidae, which are exceedingly 

 prone to die in captivity, waterbugs are very easily kept in 

 aquaria, provided that reasonable care be taken. Unless, how- 

 ever, an abundance of suitable food is provided, they will feed 

 upon each other. Separate aquaria (fair-sized jam jars answer 

 the purpose very well) should be kept for the propagation of 

 entomostracous Crustacea {Cyclops, Daphnia, &c.) for the nourish- 

 ment of Corixidae and the small larvae of the larger species ; 

 while Notoneeta and the other large species should be well supplied 

 with larvae of Ephemeridae, Sialis, small fishes, &c. Hydrome- 

 tridae will feed upon flies or small pieces of raw meat. 



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