ANIMALCULE ALLIED TO NOTOMMATA. 
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wholly distinct species, and I can easily imagine the males of other species may so 
far differ in size and apparent organization, as to have been mistaken for distinct 
races, and their physiological position overlooked. 
The absence of all organs for the sustentation of life by food leads to the belief 
that it is created for a single purpose, and that its duration or term of existence is 
very short. In this respect it somewhat resembles the drone or male bee, whose 
utility seems confined to the impregnation of the perfect female or queen. The short 
existence of this male is further proved by the fact that it is impossible to keep these 
animals alive for any extended space, and the observer who has not frequent access to 
the natural pools in which they exist, is dependent for subjects of experiment on 
their occasional production by the females in the water wherein they are confined. 
That a single impregnation is sufficient for the production of many young, is proved 
by the female continuing to breed in water in which no male can be discovered ; but 
young females so produced will not go on to develope others unless a male be born 
amongst them. 
In what light then are we to look upon an animal wanting those organs, that in the 
most elementary beings appear to constitute the almost entire structure having a single 
function to discharge, that of continuing the species, which once effected, it perishes ? 
Such indeed appears to be the case, and is another of those marvellous instances of 
endless variety in the accomplishment of a particular object by the Creator, in which 
His works abound. 
A few words are necessary as to the habitat of this curious animal. It was first 
discovered by Mr. Brightwell in 1841, in a pit immediately without the city of Nor- 
wich. For a long time it was met with in no other locality, although constant search 
was made for it in localities likely to abound in Infusoria. Even in this particular 
pond in some summers no specimens have been detected, while in others it has 
swarmed in June, July and August. It has however this year been discovered by 
Mr. King of Norwich in a pool on Mousehold Heath, within a short distance of the 
same city. I have for many years been accustomed to search the pits and ditches in 
the neighbourhood of London, and although almost every genus described by Ehren- 
BERG has furnished some species, and abundance of Notornmata, especially at Hil- 
lingdon near Uxbridge, there have been seen no specimens of this curious animal 
until by chance I detected it in August of the present year in a pond in Warwick- 
shire, not far from Leamington. As however infusorial animalcules have a very wide 
range, it is to be hoped it will hereafter be more extensively met with than hitherto, 
and more especially as from its exquisite transparency and the perfection of its ova- 
rjes and ovisacs, as well as from the discovery of a separate male, the process of 
development can be so easily watched and traced from its earliest commencement. 
As far as has been hitherto observed, the development of the ovum, through all the 
phases of germinal vesicle, granular nuclei, nucleated cell, and the conversion of cell 
into tissue, appears to follow the same type as has been so well described by Burdach, 
2 Y 2 
