14 Mr. T. Brightwell on Hirud6 geometra. 



gitudinal series of spots above and two spots underneath ; the 

 whole body, magnified, appears studded with small, dark, ir- 

 regular spots. 



Miiller says the female is sometimes filled with 300 young 

 ones. The abdomen of our species was, when captured, co- 

 vered with young, which adhered solely by the posterior disc. 

 We kept this specimen from the 24th of June to the 28th of 

 August, when it died. The young remained attached to the 

 parent during all this time, and we took some pains to ascer- 

 tain their exact number, and found they amounted to 143. 

 We never saw the parent or the young ones take any food. 

 The young differed altogether in colour from the parent, the 

 latter being a deep green, the former a Hght ash-colour : the 

 eyes of the parent could scarcely be discerned with a lens ; 

 the eyes of the young were very conspicuous, and could be 

 seen with the naked eye. The motion of this species is geo- 

 metrical, and it never swims. The abdomen of the parent had 

 no pouch, but was much expanded by the adhesion of so nu- 

 merous a progeny, so much so as to make the form appear 

 very different to the young. 



Clepsina (Sav.). This genus or family of Hirudinidce (which 

 comprises the leeches furnished with a retractile proboscis) 

 does not appear well understood. They are found adhering 

 to the undersides of the leaves of the larger aquatic plants, 

 where the small heUces (upon which they feed) abound ; they 

 are also found adhering to stones in running waters. The 

 proboscis is rarely seen exserted. 



C. complanata. We have kept many of this species during 

 the whole summer, and never saw the proboscis unless we 

 compelled the animal to protrude it, which it may be made to 

 do by a glass compresser. We have seen it devour one of the 

 common Planorbes, which it did by thrusting itself up the 

 shell of the snail and sucking the body of the animal. The 

 five-lobed stomach of the leech and of several young ones ad- 

 hering to it, were, when it left the sheU, filled with a clear 

 dark red fluid, which, contrasting with the transparent straw- 

 colour of the rest of the animal, gave it a very unique and 

 beautiful appearance. The ova of this species are first ob- 

 served to proceed from the ovary in two longitudinal rows to 

 the abdomen, which is dilated and drawn up into a kind of 

 pouch or bag to receive them. The young are gradually de- 

 veloped, and when excluded remain adhering, by their whole 

 length, for many weeks to the body of the parent. 



C, stagnalis. This little species is said to be common, but 

 we have never met with it ; all the leeches we have seen of 

 this family having six eyes, whereas this species is described 



