110 



THE NATURALIST. 



bags in the water, about the size of 

 a marble, and of a very pale yellow 

 colour, adhering to the Anacharis ; 

 in these bags they have deposited 

 their eggs, from which I hope to 

 have a good supply of young ones 

 diving out by the middle of July. The 

 Diving Spider may also be found at 

 Knottingley near Pontefract, living in 

 its diving-bell, which shines through 

 the water like a ball of silver. Their 

 singular economy was first described 

 by Clerck, in the Arcmei Suecici, 

 Stockholm, 1757, also by De Geer, 

 Mem. des Insectes, cap. 7, page 312. 

 " These Spiders," says De Geer, 

 " spin in the water a cell of strong 

 closely woven white silk, in the form 

 of half the shell of a pigeon's egg, 

 or like a diving-bell. This is some- 

 times left partly above the water, 

 but at others is entirely submersed, 

 and is always attached to the objects 

 near it by a great number of irregu- 

 lar threads." Clerck says " the 

 shining appearance proceeds either 

 from an inflated globule surrounding 

 the abdomen, or from the space be- 

 tween the body and the water." 

 The Spider when wishing to inhale 

 the air rises to the surface with its 

 body still submerged, and only the 

 lower portion of the abdomen rising 

 to the surface. It comes up for air 

 several times in an hour, though [ 

 have good reason to suppose it can 

 continue without for several days 

 together. — J. Blackburn, Leeds. 



Royal Horticultural Society's 

 Prizes. 



fTo the Editors of the Naturalist) 



Gentlemen, — I have been rather 

 amused by the article in your first 

 number on the prizes proposed by 

 the Royal Horticultural Society, 

 especially as I had a hand in the 

 protest sent to the Society against 

 them. It seemed to me and many 

 other botanists that such prizes were 

 likely to endanger the existence of 

 the rarer or more local plants, with- 

 out in any real way promoting the 

 study of scientific botany. It was 

 clear to me that they could not be 

 of any real use to the class for whose 

 benefit they were apparently in- 

 tended ; and it therefore, gave me 

 much pleasure to find that the 

 Society saw fit to reconsider them. 



Prizes given for making collections 

 of specimens to be estimated by the 

 number of species contained in them 

 are in my opinion useless, for they 

 only stimulate the habit of accuma- 

 lating objects without their study. 



If prizes are offered, I think that 

 they should be for such collections 

 as show a real knowledge of a small 

 number of plants. They should 

 consist of dissections, showing the 

 structure, either of the perfect plant 

 or of its progressive development. 

 Take for instance some genus and 

 illustrate the peculiarities and dif- 

 ferences of the species contained in 



