NEMOCEKA. 99 



become regular, perpendicular canals, which terminate-^in blind 

 ends towards the inner surface of the chorion. There are also 

 two ridges, twice as far apart as in the bluebottles, but not much 

 elevated. A deep furrow runs along upon the ridges, and the 

 arched portion by which they are united below the anterior 

 pole, and enters deeply into the chorion. The folds and 

 ridges diminish and disappear towards the posterior pole; 

 the micropyle forms a funnel-shaped pit, which is not distin- 

 guished either by a clear space, or by mouth-piece-like appen- 

 dages, and forms a distinct canal passing through the chorion, the 

 inner opening of which is connected with the vitelline mem- 

 brane. The albuminous layer of the mature ovarian egg is the 

 same as that of the bluebottle with its anterior projection. 



It is also reported that the larvse of the three last- mentioned 

 species have been found in the urinary passages, in the urethra, 

 &c. A great part of these cases are undoubtedly to be regarded 

 as illusions, and many larvse accidentally placed in the chamber- 

 pot may have been regarded as having been passed from 

 the urethra. Nevertheless it is quite possible that the larva 

 of a fly may get into the urethra, especially in blennorrhcea or 

 in sores on the penis ; or in cases of gonorrhoea uncleanliness, 

 and abundant formation of smegma, especially in hot countries, 

 these larvse may have been seated under the prepuce, and 

 hence have passed into the chamber-pot. 



The maggots of the flesh-eating flies occurring in the human 

 stomach and intestines, certainly get into the alimentary canal 

 by the use of decaying cheese, spoilt ham, and other cold meats, 

 during the latter part of the summer and the autumn. 



Upon the larvse of the flies in general, consult Von Siebold, 

 in R. Wagner's ( Handworterbuch/ 1. c., pp. 683 685. 



Sub-Order NEMOCERA. 



Corpus tenue, longum ; caput parvum ; thorax brevis, arcuatus ; 

 proboscis varia ; palpi longi, saltern 5-articulati ; sapissime 

 cristati ; antenna tenues, longa, filiformes, 6 : et ultra articulate, 

 horrida aut pennatae ; pedes tenues, longi ; alee longae et tenues. 



We should only have to do here with the true gnats ( = Tipu- 

 lida) and the Sand-flies (= Simulida = Mosquitos], of which the 

 former have a short, thick proboscis, with two distinct terminal 



