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HARDWICKE'S SCIENCE-GOSSIP. 



[Sept. 1, 1SC9. 



thrown, )n my parish of Westward. This species of 

 Speedwell, though known only a few years ago to be 

 British, is turning up in various and distant places. 

 How it is dispersed it is difficult to say. — B. W. 



MICROSCOPY. 



Cynodon dactylon. — This grass, found in 

 Cornwall, is very common in India. Powell states, 

 in his " Handbook," that " the flowers of this plant 

 present a most beautiful object, when examined by 

 the microscope. ... It is mentioned in the 

 'Atharvan Veda' as the plant with a hundred 

 roots and a hundred stems." 



Down of Wild-fowl. — We would recommend 

 collectors, when taking the eggs of wild-fowl, to 

 bring away with them some of the down from the 

 nest, for we believe that when the birds are not seen, 

 the colour and character of the down will suffice to 

 indicate the species. — Land and Water, July 31st. 



[We have urged the examination of the down of 

 birds upon microscopists as affording a new and in- 

 teresting field for research. This paragraph confirms 

 us in the conviction that great variety will be 

 found, and that the subject is well worthy of atten- 

 tion.— Ed. S.-G.] 



Expanded Zoophytes. — I have employed the 

 following method to kill the common zoophytes of 

 our coast with their tentacles expanded : — I take a 

 small saucer, such as sold at artists' colour shops, 

 and place the zoophyte in it, covering it with sea- 

 water, then float the saucer on the top of fresh 

 water in a quart basin. When the zoophyte finds 

 itself at rest, it protrudes and expands its tentacles. 

 When I think they are fully expanded, I suddenly 

 sink the saucer in the fresh water. The sudden im- 

 mersion in an unkindly fluid kills the polypes before 

 they have time to retract their tentacles. A little 

 care is required to submerge the saucer instan- 

 taneously, and the result k will be satisfactory. Of 

 course they may then be mounted in a cell with gly- 

 cerine in water. — C. 



Battledore Scales of Butterflies.— An in- 

 teresting paper on this subject, with figures of fifty- 

 three scales, by Mr. John Watson, of Manchester, 

 is published in the August number of the "Monthly 

 Microscopical Journal." 



The Ciliated Ceramium. — The Cerarnium 

 eiliatum, a thick tuft of which I obtained, is com- 

 posed of many slender much-branched threads, 

 each of which at the tip forms two hooks or curls 

 looking towards each other, a feature which is more 

 or less characteristic of the genus, and which here, 

 where it is strongly marked, imparts a very singular 

 and unmistakable aspect to the plant. The stems 

 and branches are jointed at regular intervals, and 

 every joint is quite clear and colourless in the cen- 



tral part, and purple at both extremities; add to 

 this, that at each joint there is a circle of stiff glassy 

 prickles, which stand out in a radiating manner ; so 

 that, on the whole, the species is one of the most 

 pleasing objects one can find, especially when sub- 

 jected to microscopical examination. — Gosse's 

 " Tenby." 



Adventure in a Diatom.— While examining 

 some diatomacese one day in the course of last sum- 

 mer, I chanced to be favoured with a peep at a 

 phenomenon of a most unusual and ludicrous de- 

 scription. It was one that, I presume, would have 

 greatly delighted not a few of the gullible disciples 

 of those credulous philosophers who, all regardless 

 of facts, persist in treading reverently and blindly 

 in the footsteps of the great Berlin naturalist, and 

 claim for the diatomaceas an animal nature. For 

 this once, certainly, I was almost converted, and 

 very reasonably too, for the circumstances furnished, 

 at first sight, the most convincing argument con- 

 ceivable. The gathering that supplied the above 

 was composed chiefly of Surirella gemma. One 

 specimen on the field of the microscope, to my 

 amazement, contained in its interior an animalcule 

 of the Euglena (Ehr.) genus. For a short time 

 after the diatom came into view, the imprisoned 

 Euglena was motionless, apparently bewildered, or 

 overcome with the novelty of its position. Pre- 

 sently, however, "calling home its scattered senses," 

 it began very slowly and deliberately to look about 

 its chamber of imprisonment; now elongating and 

 then contracting itself, in such a manner that if the 

 poor diatom were possessed of animal sensibilities, 

 strange indeed must have been its feelings. That the 

 animalcule was within the diatom was evident from 

 the fact that all the movements of the former were 

 limited by the walls of the latter; and at the same 

 time the changes of form and place of the Euglena 

 were accompanied with and produced correspond- 

 ing alterations of the endochrome of the diatom. 

 The question that this incident started was, how did 

 the animalcule reach the interior of the frustules, since 

 its valves and cingulum (or walls) were apparently 

 unbroken ? Can it be, after all, notwithstanding what 

 has been said to the contrary, that diatoms go in for 

 special feasts, when they prefer to dine on more 

 dainty and substantial fare than they are accustomed 

 to partake of on ordinary occasions ? Ay ! that's 

 the rub ; how came it there, poor wretch ? Thus, 1 

 think : when the drop of water which contained 

 them was covered with the thin glass, the Euglena 

 must have been under the diatom, and in contact 

 with the surface of the slide. The diatom was, from 



some cause or other, minus one valve, that nearest 

 the objective only remaining. This, with the con- 

 necting zone attached to it like a box-lid, confined 

 the animalcule under and within it. — B. Taylor, 



Whitehaven. 



