118 Miscellaneous. 



remarkable cases of the carriage of living leeches by Mammals. 

 The facts mentioned below will show that the aquatic birds, and 

 especialljf the migratory Palmipeds, can also become very active 

 agents in the dissemination of Hirudinea. 



Being installed in the spring of 1888 in the neighbourhood of a 

 large marsh-shooting in the Department of the Marne *, for the 

 ])urpose of investigating at that spot various points in the freshwater 

 fauna, my attention was attracted for the first time on the 5th of 

 April by a little leech. It was lying dead (but still fresh and suffi- 

 ciently well preserved for study) on a stone table upon which the 

 sportsmen were in the habit of depositing their game. That day 

 the bag comprised, as the result of the morning's work alone, some 

 fifteen wild duck, teal, and pintails. From that time I examined 

 all the birds killed, with the special object of discovering leeches. 

 It was only on the 8th of April that a second leech was obtained 

 upon a wigeon {Mareca peneJope, L.) among the ventral feathers. 

 This soon died. The same day, having deposited upon my work-table 

 a teal (Querquedula crecca. L.), shot flying a few moments previously, 

 great was my satisfaction on seeing emerge from the jilumage of the 

 anterior part of the breast a worm similar to the foregoing (6 millim. 

 in length). 



This specimen, which was very active, was at once isolated, and 

 two days afterwards brought alive to Paris. I was unable to study this 

 Hirudinean, owing to being engaged at the time upon the prepara- 

 tions for the fourth scientific expedition of the ' Hiroiidelle,' on 

 which I was to accompany the Prince of Monaco. Various efforts 

 which were made to feed it were without result ; it never touched 

 the living Batracbians or MoUusks which were offered it. Attached 

 by its posterior sucker, the creature swayed incessantly to and fro 

 with a rhythmic motion or moved about on the walls of the jar with 

 the well-known geometric gait {demarche geometrique) of the looper 

 caterpillars f. 



At the moment of setting out for the Azores, on the 16th of June, 

 I decided to entrust my little Hirudinean to Prof. Mouiez, who has 

 the management of splendidly arranged aquaria at the Laboratory 



* Arrondisseraent de Vitry. In order to give an idea of the irapoi't- 

 ance of this shooting, I will simply mention that the pools there occupy 

 an extent of more than 500 acres (200 hectares). On four of these pools 

 only, shooting is done from a hut, and in good seasons a skilful duck-shot 

 can kill about nine hundred wild duck (Anas boschtis, L.) there, without 

 speaking of the rest. The number of head killed has sometimes exceeded 

 two thousand, 



t It is curious to observe these two peculiarities, because each of them 

 has been the cause of a name actually applied to worms formerly con- 

 founded with this : — Hirudo oscillatoria, Saint-Amans, 1824, and Hirttdo 

 geometra^ Brightwell, 1842. This, moreover, is what O. F. Miiller says 

 of the young: — "Haro rpiiescunt, Geometrarum instar proyrcdiuntur et 

 quidem festbiante gressu''' (Verm, terrest. et fluv. . . . hist. vol. i. part 2, 

 p. 45). 



