405 



the whole of Greenland only from 30 — 40 Cows, 1 00 Goats and 20 Sheep 

 and that this handful of Cattle were located at Julianshaab on the West 

 Coast. A statement to the same effect is given by Dr. Brown himself 

 in the Manual of Arctic Instructions 1S75. p. 27. Surely if the rot still 

 exists in Greenland and has not shared the fate of so many other forms 

 of life which have finally left its inhospitable shores, we have in Julians- 

 haab a simple case and a circumscribed area Avhere on to prosecute 

 research. If the presence oï Fasciola hepatica in an isolated locality, 

 that of Julianshaab on the west coast of Greenland, is likely to prove 

 instructive, its absence from Iceland may also throw some light upon 

 the subject. Most or all of the Mollusca which iiave been or can 

 be supposed to act and suffer as »Zwischenwirthe« for the Fasciola 

 are to be found in Iceland viz. Avion ater, Avion liovtensis^ Limnaea 

 trunculata and Limnaea pevegva (see Mörch, Faunula Mollusco- 

 rum Islandiae, 1868. p. 12 and 16), as well as Planovhis votundatus, 

 if not Planovhis mavginatus. And that abundant opportunities for the 

 introduction of Fasciola hepatica into Iceland have been given by the 

 importation of sheep from abroad is learnt from what Olafs en 1. c. II. 

 p. 198 — 199, tells us as to the ascription of another sort of Sheep disease 

 to such importation. I incline to ascribe this immunity from Rot which 

 the sheep enjoy in Iceland to the habit which they in common with the 

 Shetland and Orkney sheep have of feeding between high and low water 

 marks upon the sea weed specified by 1 a f s e n in various passages 

 (I. c. I. p. 233, 279. II. p. 198 and Low, Domestic Animals of Great 

 Britain, p. 59). The Fasciola hepatica is a fresh water animal and 

 would not of course be picked up in such a locality as the interval 

 between »Ebbe und Fluth« to which the Sheep resort even in the dark 

 nights of winter. It is possible to speculate as to the virtues of salt as 

 an anthelminthian and to suggest that it may act either by enabling a 

 better gastric juice to be secreted and so giving the sheep a better 

 chance of digesting the larval Fasciola when swallowed , or by provo- 

 king a more copious flow of bile and so washing the young fluke out 

 of the gall ducts. This perhaps is not the place for such enquiries. 

 But it is a pure natural history fact that localities rich in deposits of 

 salt are favourable to the growth and health of sheep. Pallas in the 

 Avonderful II. Fasciculus of his Spicilegia Zoologica dwells on this in 

 reference to the Steatopygous variety of the domestic sheep at p. 65 

 — 67, and Avith reference to the Argali, the Ovis feva Sibevica, supposed 

 to be the parent stock of Ovis avies, var. domestica, he writes thus at 

 p. 12: »Omni vero tempore ubi possunt loca salsagine rorida quibus 

 universa Siberia abundat crebro fréquentant, terramque sale foetam 

 cavant quod cervino quoque generi solemne est.« 



