Miscellaneous. 119 



of Natural History of the Faculty of Mediciuc of Lillo. Here it 

 lived, always very active and uever feeding, until November Gth, 

 18.^8. 



The thermometer was low on the day when I obtained this leech ; 

 it had snowed the night before, and the temperature of the water of 

 the marshes scarcely exceeded 3° or A° C. This did not prevent it 

 from supporting the heat of the summer in a vessel of limited 

 dimensions, in which it had seemed desirable to leave it in order to 

 avoid losing it. The ability of the animal to resist striking changes 

 of temperature is therefore established, and the feature is worthy of 

 remark when it is a question of dissemination into waters situated 

 at distant latitudes. 



The foregoing notes, extracted almost word for word from my 

 note-book of observations, had been taken a lung time when I had 

 the opportunity of entrusting the Hirudineans with which we are 

 dealing to Dr. Kaphaiil Blanchard for the purpose of systematic 

 study. This, as we shall see, furnishes some curious results. 



To begin with, the three specimens belong to the same species — 

 Glossiphoiiia tessellata, discovered in Denmark and described by 

 0. F. Miiller in 1774:. Its geographical distribution, as at present 

 known, extends in Europe from the Arctic Circle, within which it 

 has been found in the Kola Peninsula (Russian Lapland), as far as 

 Budapest. Nevertheless it had not previously been reported in 

 France, and it is sufficiently peculiar that it should be met with 

 there for the first time upon Palmipeds. Dr. Kaphael Blanchard 

 has since obtained, in August 1890, two specimens only of the 

 species in the Erdre, near Nantes. 



This form is moreover everywhere regarded as rare, and the natxi- 

 ralists who have observed it most carefully point out a peculiarity 

 in its mode of life which is worthy of mention here. Gl. tessellata 

 crawls as it were upside down at the surface of the water in the 

 open spaces, as do the Planarians and certain MoUusks. The animal 

 is thus favourably situated for attaching itself to the migratory 

 Palmipeds, which intch (tombent), to use the technical expression, 

 and at times in numerous flocks, on the clear waters of the marshes. 



Furthermore, an observation by Dr. Weltner * shows that Pal- 

 mipeds are readily attacked by GL tessellata. At a farm in the 

 village of Wanzenau, near Strassburg, a flock of geese and ducks 

 was almost destroyed by this leech. The birds were emaciated and 

 restless and carried a certain number of these worms firmly fixed in 

 the oesophagus. Dr. Weltner believes that the leeches were searched 

 for by the birds as food, and, not having been swallowed sufiiciently 

 quickly, had attached themselves in passing down the gullet. I 

 have never met with Hirudineans in the digestive tracts of the 

 numerous aquatic birds which I have examined for the purpose of 



* Weltner, "Clepsi7ie tessellata, 0. F. Miill., aus dem Tegelsee bei 

 IJerlin," Sitzungsberichte der Gesellscii. naturforseh. Freuiide zu Berlin, 

 17 mai, 1H87. 



