Leech-lore. 357 



1817.) As we have witnessed this process we shall briefly 

 describe it. 



Some few years ago, in. the month of July, we had alive in 

 a glass vessel three or four specimens of this leech (it is the 

 only British species of Nephelis) . A few days after their cap- 

 ture we observed that one individual which had attached him- 

 self and herself — for the leeches combine both sexes in one 

 person — to the sides of the glass, appeared very restive and 

 uncomfortable, twisting and turning about in every direction ; 

 by and by a constriction was observed to take place on either 

 side of the orifice from which the eggs proceed, the space 

 between these two constrictions being much bulged out ; around 

 the circumference of this portion a slimy sloughing of the skin 

 took place, while at the same time a number of minute globular 

 bodies were emitted from the orifice, and inclosed within this 

 mucus-like formation. Then the animal, with hinder sucker 

 firmly affixed, drew back the front part of the body, and 

 slipped its head out of the jelly-like mass; and now a still 

 more curious scene presented itself. The leech turned round, 

 and with its mouth moulded this viscid secretion into that oval 

 form which the cocoon is destined to assume, and fixed it firmly 

 to the sides of the glass, leaving it for a moment, and then 

 returning to the work. This continued for the space of two or 

 three minutes, when the leech left the cocoon with its inclosed 

 vitelli to be matured into young specimens of Nephelis in due 

 time by the surrounding water. 



The Monogrophie de la Famille des Hlrudinees, by M. Moquin- 

 Tandon, is a work of great merit, and contains a vast amount 

 of information on every department of leech-lore, useful alike 

 to the naturalist and the doctor. It is accompanied with an 

 atlas of several plates, many of which are coloured, and contain, 

 for the most part, faithful representatives of the animals ; their 

 structure, mode of increase, the diseases to which the medicinal 

 leeches are liable, their commercial value, particulars necessary 

 to observe in their application, the descriptive characteristics of 

 the species of the various genera which comprise this interesting 

 group of Annelida are all carefully discussed. 



The species or varieties of the medical leech have a wide 

 geographical range, being found in nearly all parts of the 

 world, in Europe, in different parts of Africa, in East and West 

 Asia, in North and South America, and in the Indian Archipelago, 

 in hot countries and in cold, in lowlands and high ground ; a. 

 fact which furnishes evidence, when considered in addition to 

 that which results from its structure and natural habitats, of 

 the leech being an animal especially designed to serve to the 

 good of mankind. " On contemplating," says Bymer Jones,* 

 * The General Structure of the Animal Kingdom, p. 262 (1155). 



