SCIENCE- G OS SIP. 



least seven species new to science, from Italy alone, 

 in the "Bull. Soc. Ent, Ital.," xxviii. (1896); and 

 the species of two other countries have been brought 

 up to a recent date, viz. those of New South 

 Wales by Skuse in the " Proc. Linn. Soc. N.S. 

 Wales " (2), iii. (1889), and those of Argentina by 

 Arribalzaga in the " Revista del Museo de la Plata " 

 (1891). 



The British Museum collection, though very. 

 deficient in many sections of the Diptera, contains 

 a good series of a large number of species of 

 Culiciclae, including all Walker's types. Mr. 

 Theobald is, I believe, now engaged on revising 

 the Museum material in this group. The study of 

 all species outside Europe and North America • 

 would be well repaid by the definite fixing of their 

 synonymy. 



The following genera are recognised : Culex L., 

 Megarhinus St. Farg., Aecles Mg., Anopheles Mg., 

 which occur, speaking broadly, all over the 

 ■world; Moclilonyx Lw. appears to be confined to 

 Europe; Psoropliora to North and Central America ; 

 Corethra Mg. extends from Europe to at least 

 Manila aud New Zealand ; Plettusa Phil, is a 

 genus of several species from Chili ; while Arri- 

 balzaga's genera Oehlerotatus, TJranotaenia, 

 Taeniorhynchus and Janthinosoma occur in South 

 America and Honduras, the remaining genera 

 being Heteronyclw of Skuse from New South 

 Wales, Sabethes of Rob. Desv. from Brazil, 

 and Saemagogus of Williston from St. Vincent. 



Our British species are few in number, totalling, 

 according to Mr. Verrall, sixteen certainly in- 

 digenous, with three additional, requiring further 

 •confirmation. 



Although European species in general, and 

 British species in particular, cannot compete with 

 those of other countries in point of size and vigour 

 of attack, such as the Megarhinus ferox of the 

 West Indies and a gigantic species three-quarters 

 •of an inch long in my collection from Natal, the 

 presence of female Culicidae on our shores is often 

 painfully evident. Though the bites are suffi- 

 ciently irritating to commend any researches that 

 may lead to the limitation of the specimens within 

 reasonable numbers, the discovery of the important 

 part played by many species in the spread of 

 malaria gives a more vital interest to experiments 

 that may suggest means to enable us to hold them 

 in check. 



Mr. Nuttall, of Cambridge, has been occupied 

 for some time now in investigating the coincidence 

 of the present localities of Anopheles in Britain 

 with the former areas of malaria ; and all ento- 

 mologists might assist to the extent of keeping a 

 casual look-out for this genus, capturing the speci- 

 mens and recording date and exact habitat, which 

 is usually an outhouse, outdoor closet, or similar 

 place. 



In spite of being on the watch during the two 

 months of August and September last year that I 



spent at Hunstanton in Norfolk, I failed, as I 

 thought, to find a single example ; but on disposing 

 of a box of odds and ends found there, one Ano- 

 pheles macullpennis was discovered. It was taken 

 on October 1st, this being my sole capture of a 

 member of the genus. 



Anopheles may be recognised from Culex, apart 

 from structural differences, by the position of the 

 insect when at rest. In the case of the latter 

 genus the body of the insect is approximately 

 parallel to the surface on which it is resting, the 

 two hind legs being raised above the body, the 

 tibiae and tarsi held straight out behind hori- 

 zontally, only the four anterior legs touching the 

 resting-place. In Anopheles also only the four 

 anterior legs touch, but the head points nearly 

 vertically to the object, as if the proboscis were 

 about to penetrate it, the rest of the body being 

 always in a straight line with the head, and thus 

 at nearly right angles to the resting object. The 

 posterior femora are not raised above the abdomen, 

 as in Culex, but lie along its sides, whilst the 

 tibiae and tarsi stick out behind in a curve up- 

 wards. 



It is, of course, generally known that only the 

 female gnat or mosquito bites, and that this sex 

 may be easily distinguished from the male by the 

 absence of the very feathery antennae which cha- 

 racterise that sex. These organs in the female are 

 only sparsely covered with a few regularly placed 

 long hairs. 



The eggs are laid in stagnant water, in which 

 medium the air-breathing larvae live their short 

 lives, and there the pupae also remain, floating on 

 the surface. Several generations occur in a year, 

 and they hibernate as perfect insects. 



In Mr. L. 0. Howard's valuable paper, before 

 referred to, the life history is given in full of some 

 of the species ; but it is evident that in at least 

 some others the economy is of a different nature, 

 as he records that the larvae of Psoropliora ciliata, 

 a widely distributed and very peculiar North and 

 Central American species, could not be bred to 

 maturity under the same conditions that were 

 favourable to the development of several species 

 of Culex. 



Protective measures against the attack of mos- 

 quitoes seem to have been only partially successful. 

 Most of the species apparently possess, not only 

 considerable vitality, but a kind of special adapt- 

 ability to widely different environments. The brevity 

 of the life cycle necessitates almost ceaseless 

 continuance of the remedial applications to check 

 abundance, especially in warmer climates, such as 

 in the Southern States of North America, where 

 they are prevalent luracticaHy all the year round. 

 Tar, kerosene, salt, petroleum, creosote oils, per- 

 manganate of potash, and many other remedies 

 have been adopted in experiments to destroy the 

 larvae ; but many of these agents have met with 

 but indifferent success. From the recorded reports, 



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