LEECH CULTURE. 835 



Eastern Massachusetts, including the southern part of Cape Cod, were formerly noted for the 

 large numbers of Leeches they contained, and during the early part of this century,many Leeches 

 were collected from them for medicinal purposes. Philadelphia is now the only large city where 

 American Leeches are used by physicians, who prefer them to the European for certain kinds of 

 treatment. The latter Leech is the more powerful, and extracts the most blood. According to 

 the statements of Philadelphia leechers, about four American Leeches are required to do the work 

 of one European, and the chief merit of the former arises from the fact that thej' can be used more 

 freely and with less danger to the patient, and can also be employed, on the more delicate parts 

 of the , body, where the European Leech would act too vigorously. They are especially recom- 

 mended for the region about the eye, and several are sometimes used, distributed over a wider 

 space, when it is thought best not to extract the blood from a single spot by the aid of an 

 imported specimen. The American Leech does not attiich itself as rfeadily as the foreign, and often 

 several specimens have to be tried before one can be found to fasten itself. They bite much less 

 readily out of water than in. The bites of the two Leeches are~ different; that of the European 

 being deeper and more pronounced and bleeding much longer after the Leech has been detached. 

 The wound of the American Leech generally closes very soon after the Leech has been released, 

 and sometimes immediately. 



The European Leech. — The European Leech belongs to a different genus from our own, Hirudo, 

 and by some authorities is considered to constitute two distinct species, H. medicinalis, the Gray 

 Leech, and H. officinalis, the Green Leech. By others the Green Leech and Gray Leech are place(^ 

 in the one species, H. medicinalis of Linnaeus. "They are both marked with six longitudinal 

 dorsal ferruginous stripes, the four lateral ones being interrupted or tesselated with black spots. 

 The color of the back varies from a blackish to a grayish green. The belly in the first variety is 

 of a yellowish color, free from spots, and bordered with longitudinal black stripes. In the second 

 it is of a green color, bordered and maculated with black. This Leech varies from two to four 

 inches in length. It inhabits mai-shes and running streams, and is abundant throughout 

 Europe." 



Pridr to thirty years ago nearly all the northern countries of Europe contained Leeches, but 

 most of the supplies came from Sweden, Eussia, Poland, and Hungary. The swampy regions in 

 which they lived were drained from time to time, for one reason and another, until finally vast 

 areas which had once been profitable became dried up, to the almost entire destruction of the- 

 Leeches. Then, and for the first time, was the extent of the injury fully realized over all Europe,, 

 and streuuous efforts wfere made to remedy the evil. Several governments, including the French,. 

 Prussian, and Hanoverian, offered premiums for successful results in leech-culture, but these 

 efforts were rewarded only in the former country. At present the larger share of the Leeches 

 used in Europe and this country come from the artificial ponds or meadows of Southern Prance,, 

 although many are also raised in Hungary and in other countries of Southern Europe. Paris is. 

 the principal receiving center, whence they are sent to England, to the English colonies, and 

 the United States. The export trade to South America and the West Indies is largely carried, 

 on through the United States. 



Leech culture. — The localities selected for leech-raising are swampy meadows, where the- 

 bottom is more or less firm and solid. A certain area having been chosen, it is divided inta 

 rectangular plots of different sizes by means of ditches. The breeding season is in June audi 

 July. At this time water is admitted only into the ditches, the meadow flats remaining dry.. 

 The eggs are laid in the loose, swampy soil at the margins of the ditches, and when the young; 

 creep out about six weeks, more or less, afterwards, the meadows are overflowed artificially to a. 



