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SCIENCE-GOSSIP. 



Symbiosis and the Microscope. — I have recently 

 been reading an article in the " Transactions of 

 the Leicester Literary and Philosophical Society " 

 for October last, by Mrs. Nuttall, upon "Symbiosis 

 in Plant-Life." Can she or any of your readers 

 give me some instructions as to how to proceed to 

 study this remarkable phenomenon in some 

 manner easily attained in this country ? She cer- 

 tainly mentions some experiments in her paper, 

 but not so explicitly as one would desire. Will 

 some one give us particulars of his or her own 

 work on this subject ? That is to say, describe the 

 mode of investigation with the aid of a microscope, 

 and if we can do it in an average English home. — 

 Charles Johnson, Water Street, Liverpool; December, 

 1895. 



Nymphon Gracilis. — Whenever I latterly 

 brought home a supply of the seaweeds Ulva or 

 Entermorpha for the tank, I found numbers of tiny 

 specimens of Pycnogonidas, though of what species 

 I could not determine, probably Nymphon gracilis. 

 They seemed very lively and hardy, and were 

 continually waving their long, spider-like legs 

 about, apparently without any particular object. 

 Under a moderate power of the microscope it was 

 easy to see the eight-jointed legs, each ending in the 

 formidable pincers, the blind tubes (five pairs) 

 running from the stomach to the limbs and chelicerae ; 

 the jointed mandibles and the pointed rostrum. I 

 am anxious to obtain further information on this 

 group, and should be much obliged if any of your 

 readers could tell me of any books on the subject. 

 ■ — Catherine A. Winckworth, 11, Old Steine, Brighton. 



Interesting Microscopic Object. — The seed 

 of Collonia grandiflora affords an excellent illus- 

 tration of spiral fibre in cells, and as it may be 

 readily obtained from any large seedsman, all 

 microscopists who have not already examined a 

 specimen should do so at the first opportunity. 

 To observe this under the microscope, cut a thin 

 slice transversely and place on a glass slide ; cover 

 with thin glass ; get into position on stage and 

 focus ; then put a drop of water on top of cover 

 glass so that it may flow under same to the section 

 of seed. The instant it reaches this, the spiral 

 fibre will dart out in all directions. If desired, the 

 specimen may afterwards be mounted in glycerine 

 jelly as a permanent object. Use a one-inch 

 objective, and dark ground illumination. — J. C. 

 Webb, 32, Hensloive Road, Dulwich. 



Micro-botany in Norfolk. — After rain last 

 year, and many times since, I have found immense 

 quantities of the pretty little desmid Cosmarium 

 botrytis in the water-troughs of my house. They 

 grow in large patches of a beautiful light-green 

 colour, and it is quite easy to obtain clean 

 collections. In the same place, I found Raphidium 

 fulcatum, one species of Oedogonium and one or two 

 Oscillarice. The drains running through a peaty 

 meadow in my neighbourhood look extremely odd, 

 owing to the abundance of Lyngbya ochreacea, which 

 oozes out from the wet sides of the drains in 

 several places. It makes the bottom of the drains 



look as if covered with a layer of iron rust. A 

 shallow dirty pool close by is green with Eugleneae. 

 Kerner appears to class these with the Algae in 

 " Natural History of Plants," vol. i. I was greatly 

 astonished, the first time I examined them, to see 

 the apparently fine specimens of Protococens begin 

 to glow in one spot in each, like rubies, and then 

 to elongate and rapidly swim about. — /. Leivton 

 Brain, Swanton Morley, East Dereham. 



Interesting Leeches. — In May last, in one of 

 my aquariums, I had several small leeches ; they 

 were milky white, about three-quarters of an inch 

 long when moderately extended, " margin crenate," 

 as a botanist would say. The interesting part about 

 them was, that the body, rather further back than 

 the middle, was broadened with the back convex ; 

 on the under side it was concave, making a hollow 

 in which a number of young lived for several weeks. 

 The young ones were shaped exactly like the parent, 

 as probably it was, and of the same colour, but had 

 two black spots, doubtless eyes, at one extremity, 

 and a sucker at both extremities. When the 

 parent extended itself in order to progress in the 

 usual manner of leeches, of course the cavity 

 underneath was lessened, and the young crowded 

 together, stretched out their heads on both sides 

 and moved them about, giving a very peculiar 

 appearance to the whole. With some difficulty I 

 detached a number of the small ones, and there 

 was certainly more than twelve — perhaps as many as 

 twenty of them. They made capital popular micro- 

 scopic objects, and lived for a considerable time 

 in the aquarium. Gradually all disappeared, 

 possibly falling a prey to other inhabitants of their 

 home. I have not been able to find a description 

 of anything of the kind in the books to which I 

 have access ; perhaps some reader better provided 

 would kindly give information. — /. Burton, g, 

 Agamemnon Road, W. Hampstead. 



Pond Life under Ice. — I generally have all the 

 year round, at least a Melicerta or Limnia ready to 

 place upon the stage, but was not quite prepared 

 for the following. Our canal was frozen over 

 early in 1895, some weeks, with ice quite seven 

 inches thick, so my supply of weed was cut off. On 

 February 27th I was told the city council's men, 

 with an iron boat drawn by four horses, were 

 breaking the ice for the purpose of rendering the 

 canal navigable. I proceeded there, and as 

 opportunity offered managed, from between the 

 big blocks of ice, to fill my can with weed, and was 

 surprised to find a good lot of healthy Melicertas, 

 Limnias and Vorticella. Stephanocerous eichornii was 

 found in fair numbers and in good health, continu- 

 ing to breed for some time. Volvox, being of the 

 vegetable kingdom, may not have been such a 

 surprise to me, but I was much interested by their 

 behaviour during the same cold period. On 

 October 1st, 1894, I brought home an ordinary 

 light ounce medicine bottle full of water, with a 

 fair sprinkling of Volvox, which increased wonder- 

 fully. A shady place out of doors I found to suit 

 them best. When the hard weather came I omitted 

 to take the bottle indoors, and one morning found 

 the water had become a solid block of ice and the 

 bottle burst. I proved the block to be frozen 

 through by breaking it in pieces. The pieces were 

 then placed in a basin to thaw-, and the Volvox were 

 found to be in as good condition as before. The 

 water containing them was poured into a fresh 

 bottle, the freezing process being repeated. They, 

 however, did well, and continued to live with me 

 until the end of March, 1895, when they disappeared. 

 — John Stevens, 1, Friar's Walk, Exeter. 



