BRITISH HYDRACHNID^. 145 



plants, and on the sides of the glass tank, a batch of eggs at one 

 time in a gelatinous film. Second we have the larval form, see 

 Fig- 3> gj which is very unlike the adulr, and is hexapod. Thirdly, 

 we have the nymph. I have taken several of what I believe to be 

 Nescea in this stage ; they have eight legs, but only two pores in 

 a special plate, on each side of the genital fissure, but with my 

 present limited knowledge I should not like to say to what species 

 of Nes(ea these different nymphs belonged. How long a time they 

 exist in their various stages, and how many times they change their 

 skin during these periods, are questions yet to be answered. 

 Fourthy, the imago or perfect mite. 



It will, perhaps, be interesting to give particulars of the develop- 

 ment from the egg to the larval stage of Nescea carnea, so far as 

 my own observations have gone. 



The Quekett Club during the summer months have an excur- 

 sion every fourteen days to interesting collecting grounds round 

 London, which is a great boon to members who live in London, 

 and are engaged in business all the week. On May i8th, 1895, 

 the excursion was to Staines. On Staines Common there are a 

 number of small ponds, and from these ponds I took a number of 

 water mites, which I believe to be Nescea carnea (Koch). This 

 mite is rather large, and of a deep maroon colour, long oval in 

 shape, and the eyes stand out on two prominent swellings, which 

 seems almost colourless compared to the rest of the body (I was 

 not fortunate enough to take a male N. carnea). 



On reaching home, I separated all the Nesaa carnea from 

 other mites which I had collected, and put them into one small 

 glass tank which stands on my window-sill, and next morning I 

 found that a quantity of eggs had been laid on the water plants 

 and the sides of the tank. I then took out three or four mites 

 with a dipper, and put them into a small trough, and on the 

 morning of the 20th I had the satisfaction of finding a batch of 

 eggs laid in a most convenient position for microscopical examina- 

 tion. I again removed the mites and put the trough in position 

 under the microscope, and examined the eggs at every opportu- 

 nity. At first, they had the appearance of Fig. 3, orange red in 

 colour, and embedded in a film of gelatinous matter, of a pale 



International Journal of Microscopy and Natural Science. 

 Third Series. Vol. VI. k 



