194 The Exaynination of Noherfs Nineteenth Band. 



undisturbed state, the Gnat must be secured as it is seen issuing 

 from tlie larva ease. The scales should also be mounted dry, as 

 when immersed in balsam or fluid they become too transparent. 

 They are an excellent test for a i-inch objective. 



It is not improbable that the scales of even the various species 

 of Culex will, after a more careful examination than I have been 

 able to make, be found to differ, as upon going over the collection of 

 Gnats in the British Museum, I discovered the scale represented at 

 Fig. 8. This form closely resembles the scales of Lepidoptera. 



The body of C. aimulatus is entirely covered with alternate rings 

 of dark brown and white-coloured battledore scales ; and the hairs 

 projecting from its sides are longer and more numerous than in 

 C. inpiens or C. musquito. The "feathered antlers" pectinate 

 antennae of the male insects, although destitute of scales, are exceed- 

 ingly handsome objects : they surmount the most brilliant set of 

 compound ocelli it is possible to find. In short, he wears finer 

 clothes and is better dressed throughout than his female companion. 

 When the piercing apparatus is sent into the flesh of a victim, the 

 proboscis appears to divide, it is then thrown up and turned back 

 upon the head like the trunk of an elephant. _ 



The Gnat-like midges, so common in this country, and which 

 belong to the Tipuhdfe, very closely resemble Culicidse. Chironomus 

 2>lumosus, often mistaken for a Gnat, has plumed antennae ; but on 

 no part of wings or body can scales be found ; the same remark 

 applies to the rest of the species. The resemblance between many 

 of the perfect insects belonging to the genus is striking, while 

 their larvae differ very considerably from each other. The club- 

 shaped balancers, halteres, are more developed in Tipula than in 

 Culex. The genus Psijehoda have been thought to be clothed with 

 scales, however they are not ; their wings and bodies, on the contrary, 

 are thickly covered with long, pecuhar hairs. Some of these little 

 creatures present under the microscope a gorgeous appearance. 

 The various parasites infesting Diptera deserve the attention of 

 microscopists. 



VII. — T]ie Examination of Noherfs Nineteenth Band. 

 By F. A. P. Baenard, of Columbia College, New York. 



A PARAGRAPH in the article " On the Use of the Nobert's Plate," 

 by my friend Colonel J. J. Woodward, of Washington, published 

 in the July number of the Journal, which has just reached me, 

 deserves some notice. The paragraph is upon page 27 of the 

 Journal, and relates to a plan employed for settling the question 

 whether the lines seen by me in the nineteenth band of Nobert's 

 plate, in a series of observations made some years ago, were true or 



