46 



HARDWICKE'S SCIENCE-GOSSIP. 



[Feb. 1, 1867. 



Movements in Diatoms. — On the forenoon of 

 December 25, 1866, I took a small gathering of 

 diatoms, comprising Campylodiscus spiralis and 

 Pinnularia viridis. In several specimens of the 

 latter, I noticed an unmistakable movement of large 

 oily-looking globules, or granules, of which I 

 counted from two to six in each half of the several 

 individuals I examined. This movement was of a 

 trembling and oscillating character, not unlike the 

 granular movement which may be seen going on in 

 the ends of Closterium lunula, except that in the 

 diatoms in question the granules did not retain the 

 grouping and rapid motion which distinguish them 

 in the former, but passed at slow intervals through 

 about one-fifth the length of half the cell. This 

 granular activity could not, I think, be an error of 

 observation ; for I noticed it in many specimens, 

 some of which were watched by me very closely for 

 a considerable length of time. Nor could it be 

 occasioned hy the diatom's proper movement through 

 the water, because some of the forms in which I 

 observed it were not moving, but were perfectly 

 stationary at the time. I shall be glad to know if 

 any other readers of Science Gossip have observed 

 this movement ? — B. Taylor. 



Daisy Anemone (Sagarlia bellis). — I have 

 had two very curious specimens of Daisy Anemone, 

 born in one of my aquariums lately, one having three 

 distinct heads, each with its proper amount of 

 tentacles, which I have named Cerberus, and 

 another two. Is this an unusual circumstance ? I 

 think it must be, as Mr. Gosse does not mention it 

 in any of his books. — E. J. J. 



Lopping Trees. — Can any of your readers tell 

 me if the following lines in Tusser's " Eive Hundred 

 Points of Good Husbandry " are founded upon fact ; 

 and if so, what is the scientific explanation ?— 



" In lopping old Iocham, for fear of mishap, 

 One bough stay unlopp'd, to cherish the sap ; ' 

 The second year after then boldly ye may, 

 For dripping; his fellows that bough cut away." 



And again, — 



" For sap, as ye know, 

 Let one bough grow j 

 Next year ye may 

 That bough cut away." 



Also the reason for the following assertion : — 



" Pluck broom, broom still; 

 Cut broom, broom kill." 



F. A. A. 



Cat and Cockroaches. — Our house was per- 

 fectly free from cockroaches till June last, when we 

 got a kitten, and immediately the cockroaches ap- 

 peared. The cat showed peculiar enmity to them, 

 and used to hunt and eat them by the dozen every 

 day; and always after being fed, she would go 

 under the grate to hunt for them. Some weeks 

 back she, having been ill for a long time, was taken 

 away ; and from that very day the cockroaches dis- 

 appeared also, one solitary individual having been 

 seen on one occasion since ; and since he came to 

 grief, not one has appeared. Can there be any con- 

 nection between their disappearance and the removal 

 of the cat ? It seems more than a coincidence, and 

 her enmity to them makes it remarkable. — M. A. 



Cats and Rain.—" Cats sitting with their backs 

 to the fire an indication of rain." Can you inform 

 me in your next number if the above statement is 

 but vulgar gossip, or whether it is a scientific 

 truth ? If the latter, on what grounds ? — W. B. B. 



Blackbirds. — Whilst my children were feeding 

 the birds yesterday morning, our cat came down 

 upon and devoured a fine cock blackbird. Three 

 hen blackbirds (I believe of the same brood) wit- 

 nessed the circumstance from neighbouring trees. 

 As soon as Tom had finished his meal and departed, 

 they gathered ,up the scattered feathers of their 

 brother, and carried every one of them away 

 amongst the trees of the garden. Was this done 

 from sisterly affection, or from an instinctive feeling 

 of reverence for the dead ? — Ben. Snow. 



Halo op a Shadow. — Permit me to corroborate 

 the statement of the Rev.- J. S. Tute, as to the halo 

 of a shadow. I experienced a remarkable instance of 

 this, one fine spring morning in 1S65. Two friends 

 and myself had started at five o'clock for a walk, 

 just as the sun rose above a hill on our right, casting 

 our shadows on to the slope to the left below, some 

 fifty yards off. Our gigantic figures seemed to be 

 surrounded by a " nimbus " of brilliant light, 

 extending at least a foot and a half all round. The 

 young whe^; on which our shadows were projected 

 was drenched with dew, and the reflection from the 

 drops, each sparkling like a diamond, no doubt 

 produced the appearance described. I have fre- 

 quently seen it since, but never to equal this occa- 

 sion. — Daydon Jackson. 



Halo of a Shadow. — This curious phenomenon 

 (Science Gossip, p. 23) is quoted also in " Ksemtz's 

 Meteorology," chap. xix.,under the name oUAnthelie; 

 and J. S. T. is quite right in attributing it to 

 diffraction : — " When the sun is near the horizon," 

 says K., " and the shadow of a person falls on grass, 

 a field of corn, or any surface covered with dew, an 

 aureola is observed around this shadow, the light of 

 which is the strongest at the head ; this light is 

 owing to the reflexion by the stalks or straws, the 

 dew-drops, or the vesicules of a mist lying in low 

 strata on the sea. It is the brightest around the 

 head, because the stalks situated in the proximity of 

 that part of the shadow show all their enlightened 

 sides, while other stalks that are farther show en- 

 lightened parts and others that are not ; the stalks 

 being cylindrical, the aureola is somewhat larger in 

 the vertical sense." Praunhofer attributed all this 

 to diffraction, and observations confirmed his theory. 

 When reflected beams pass through other vesicules, 

 these beams are also diffracted, and coloured rings 

 are the result. Anthelies were observed in the 

 Polar seas by Captain Scoresby, &c. (more parti- 

 culars vide Ksemtz). — B. Melle. 



Double Shell of Eggs. — A gentleman in 

 Cumberland had a hatching of the eggs of the 

 Moscovy duck sent him; one, from its very large size 

 (it weighed over five ounces), was supposed to 

 contain a double yolk, and was therefore broken for 

 domestic purposes, when a second shell was dis- 

 covered inside. The enclosed egg was of the 

 ordinary size and appearance. The interval between 

 the shells was filled with a fluid resembling the 

 ordinary white of egg, but rather thinner.— W. Gain, 

 Tuxford, Notts. 



Cordon Bleu. — In answer to a query, Science 

 Gossip, vol. ii., p. 262, I said, p. 283, Ampelis 

 cotinga was cordon bleu; I found since, another 

 bird has also that name, viz. the Sucrier gamtocin, 

 Cynniris collaris, Vieil.— cordon bleu of Levaillant 

 {vide Lev., " Hist, des Ois. d'Afrique," Tl. cexcix., 

 pp. 1, 2). -B. Melle. 



