440 Hey : Boulders at Ayton. 



into the delicate pseudopodia. Tlie adhering- syrup is removed 

 by blotting- paper and by washing- in concentrated glycerine, 

 which is quickly removed by blotting paper, and the rest washed 

 off by absolute alcohol, and the dry animal finally mounted in 

 Canada balsam. Glycerine might be used instead of syrup, but 

 gives rise to more objectionable back diffusion. I cannot pretend 

 to describe all the necessary detail, which must to some extent 

 vary with the particular species of worm, but I may say that, 

 when all is properly carried out, surprisingly good objects can 

 be obtained showing the most minute blood vessels, like exquisite 

 injected preparations, and far better than when the animals are 

 alive. The character of these vessels varies greatly in different 

 g-enera, and there is a marked and characteristic difference in 

 different species of the same genus. So far I have seen no reason 

 to think that the specimens will deteriorate by keeping, since those 

 made three months ago are as good or better than they were at 

 first. I have applied this system to very few other animals than 

 Annelids, but possibly some modification of it may turn out 

 valuable in other cases by getting rid of all the contained water 

 by diffusion under antiseptic conditions, without risk of decom- 

 position. 



I trust that what I have now described will, at all events, 

 show that there is a wide field for research in connection with 

 my subject outside the ordinary routine methods of biological 

 study. 



GEOLOGY. 



Boulders at Ayton. — As I was recently walking up a lane 

 which runs from East Ayton to Seamer Moor, the roadmen 

 called my attention to a large boulder which had just been 

 rolled out of an adjacent field, having been struck by the plough. 

 I had it moved to my garden, and turned the hose on it, when it 

 proved to be a fine mass of Shapfell granite (confirmed by 

 Mr. P. F. Kendal). Its dimensions are about 20 x 18 x 12 in,, 

 and the men who moved it said it weighed over 20 stones. It 

 occurred on rather high ground where an excavation made 

 some years ago shows that about nine feet of glacial sands and 

 gravels rest upon the Corallian rocks. I have not seen a large 

 mass of Shapfell granite at Ayton before ; basaltic boulders are 

 the commonest, and fine grained granite also occurs, as well as 

 one rich in iron pyrites. — W. C. He^ . 



Naturalist, 



