76 A PKODUCTrVE POND. 



A PKODUCTIVE POND. 



At the recent conversazione of the Birmingham and Midland 

 Institute, one of my correspondents, to whom I had sent some Melicerta 

 ringens from here, introduced himself to me, and incidentally mentioned 

 that he had found Conochilus volvox very abundant in a pond near 

 Redditch. (See his letter, S.S.R., Redditoh, in " Midland Naturalist," 

 page 50.) As I had only seen this interesting rotifer once before, (at a 

 soiree of the Quekett Club,) nor ever heard of its having been found in 

 this neighbourhood previously, I gladly made an appointment to visit 

 the pond, which I did on the foUoviing Saturday. I was much pleased 

 on the first dip to find many specimens in my bottle, and I hastened, as 

 time pressed, to carry home as many as possible. Of these I sent a 

 bottle, containing nine groups, to a correspondent at Croydon, (a twenty- 

 four hours' post,) of which only two groups survived the shaking of the 

 journey, the individual rotifers, of which the groups consist, being so 

 easily separated. After this I found my stock very rapidly disappeared, 

 owing, (I attributed) to the number of larvae and entomostraca which I 

 had imprudently allowed to remain with the rotifers, and I, therefore, 

 decided to pay another visit to Redditch. This time, as I was care- 

 fully examining the water at the pond side, I found a number of Melicerta 

 on the duck-weed, of which I brought home a small quantity to my 

 friend's house. It was a surprise to him, as he had, up to that time, 

 overlooked it. As soon as he recognised the object, by the aid of his 

 pocket lens, he called my attention to the large size of the pellets, of 

 which the cases were built up. On reaching homo I put the Melicerta 

 under my compound microscope, and was surprised to see how marked 

 a difference there was in the size and shape of the pellets as compared 

 with those of the Melicerta I find in the pool here. The pellets of the 

 latter have, where they project from the exterior of the case, a nearly 

 hemisphexncal surface, whereas those of the specimens from Redditch 

 appear to cover the case with small cones, nearly of the shape of sugar 

 loaves ; and on further examination I also see a great difference in the 

 shape of the pellet cup, quite equivalent to the different shape of the 

 pellets. I cannot help thinking this is a variety of Melicerta distinct 

 from the one I have usually found. I have sent specimens to F. A. 

 Bedwell, Esq., and to Dr. Hudson, for their opinion. Further examination 

 of the duck-weed, from Redditch, showed me that it abounded with 

 another rotifer I had never found before, Cephalosiplwn limnian, figured by 

 Dt-. Hudson in the October, 1875, number of the " Monthly Microscopical 

 Journal ;" and curiously enough I also found a single specimen of what 

 I call Clicetospira cylindrica, which he figures in the same plate as 

 Archimedea {Chatospira?) remex, and which he had found associated on 

 the same weed f.4nac/irtri«j with the Cephalosiphon limnias. This iufusoriau 

 I found here (the Hyde Pool) in August, 1872, on Myriophylhun, and it 

 was named by Mr. W. Saville Kent, to whom I sent specimens, 

 Chatospira cylindrica. I still further found on this duck weed, amongst 

 other infusoria, many specimens of Vaginicola dccumbens and Epistylit 

 natans. Subsequently I found three Tardigrada, or water bears, diligently 

 creeping about, and tugging away at the decaying portions of the Lcmna. 

 I cannot help saying I have seldom come across a locality of better 

 promise to a naturalist taking any interest in pond life. — Thomas Bolton, 

 Hyde House, Stom'bridge. 



