BRITISH HYDRACHNID^. 315 



home, if the water is kept in good condition with pond weed. I 

 have been fortunate enough to breed the larva. On June ist this 

 year I put a dozen Diplodontus despiciens adults into a tube by 

 themselves, and on June 4th a quantity of ova was deposited on 

 the side of the tube. The eggs or nuclei were embedded in an 

 outer protoplasmic matter, in the same manner as I described in 

 the paper on JVescea. They were of a deep cadmium colour, the 

 gelatinous-looking film being almost colourless. They passed 

 through similar stages to those previously mentioned, and 

 hatched out on June i6th. Their first object in life seemed to be 

 to get out of the water and into the world as quickly as possible ; 

 they ran about like so many minute red spiders. 



The movements of these little creatures were much more 

 energetic out of the water than in, and I found some difficulty in 

 getting one into a suitable position to draw (Fig. 4 is drawn from 

 one in the life). It has four eyes on the dorsal surface, as shown 

 in the drawing ; six legs only, which is usual in the larval stage ; 

 the tarsi is broad at the widest part, and thin at the claw end ; the 

 claws; two in number, are curved backwards (see Fig. 6) ; the tarsi 

 is covered with a quantity of long pectinated hairs. The colour 

 of the larva is pink. Palpus is chelate, same as adult. 



I have not been able to carry my investigations further than 

 the larval stage, but have taken several specimens of the nymph, 

 which is supposed to be the next stage, at Bealings this year 

 (Fig. 3, in which note the arrangements of the genital pores) ; and 

 at some future time I hope to be able to note and describe the 

 whole life-history of these very interesting creatures from the ova 

 to the adult. 



Krendousky, in his work 1878, gives a very good outline 

 drawing of the larva of this Hydrachnid. Miiller's small figure 

 of the adult is very good. Newman's figure is a beautiful drawing 

 in colour, with red body and yellow legs. 



EXPLANATION OF PLATE XVI. 



Diplodontus despiciens (Miill.). 



Fig. 1. — Ventral surface of adult. 

 ,, 2. — Dorsal surface of adult. 



