OCCASIONAL NOTES. 269 



ascertain respecting the food of sea fishes and what it is that influences 

 these various migrations. — Francis Day (Pittville, Cheltenham). 



Dogfish on the Coasts of Sligo and Mayo. — Dogfish in immense 

 numbers have this season invaded the fishing-grounds off Killala Bay and 

 the adjacent coasts ; indeed so large have been the " schools " that fisher- 

 men speak of seeing acres of them, and owing to their voracity and 

 numbers have seriously injured the coast fishings for some weeks past, 

 more especially the Mackerel fishing ; for although a ground fish, they rise 

 to the surface and attack the Mackerel or Herrings suspended in the drift 

 nets. Some eight or ten days ago, off the Sligo coast, the crew of a fishing 

 boat shot their nets into a " school " of Mackerel, and a most successful 

 haul was made ; but to the great disappointment of the fishermen, on taking 

 their nets on board, it was found that of nearly two thousand Mackerel 

 taken, only two hundred were marketable, the remaining fish being so bitten 

 and disfigured by the Dogfish as to be unsaleable ; and as the marketable 

 fish were sold for 18s. per hundred, the feelings of the men at such a loss 

 may be better imagined than described. It appears that the Dogfish 

 have thus come in-shore for the purpose of producing their young, and 

 their presence has not only stopped the drift-net fishing, but has inter- 

 fered also with the long-line fishing. The fishermen say that until these 

 fish have left, it will be useless shooting either nets or lines. It will be 

 interesting to know whether other parts of the coast have been similarly 

 visited by Dogfish this season. — Robert Warren (Moyview, Ballina). 



On a Leech found in Cornwall. — On May 12th, I found in a little 

 rill at Tremeader, springing out of the granite rock of Zeunor Hill, near 

 Penzance, which rill makes its way through a total course of less than a 

 mile to the sea, over a clear pebble bottom bordered by ordinary vegetation, 

 a large Leech (either a Horse Leech or the Black Leech, probably from its 

 decided colour the latter). I searched the rivulet for a considerable distance 

 up and down, but could find no trace of animal life in it except this Leech 

 and some tadpoles. The bed of this rivulet is throughout of a sandy 

 nature, without any suspicion of a muddy bottom anywhere. There are 

 leeches in ponds in this district, but the nearest that I know of are many 

 miles away from this Tremeader rivulet, and spearated from it by a granite 

 watershed. Of course the question is, where did this Leech come from ? — 

 Thomas Cornish (Penzance). 



[Some Leeches are parasites on fishes ; the specimens in question may 

 have been transported in this way, but without seeing it, or having a more 

 detailed description, we cannot express an opinion. "Horse-Leech" is a 

 name given to two distinct species, or even genera — Hcemopsis sanguined 

 and Aulostomum gulo. — Ed.] 



