HA RD WICKE'S SCIENCE- G OSSIP. 



257 



Rub down in a mortar the gums, with a little water 

 gradually added ; add the tincture guaiacum, and 

 shake up in a wide-mouthed bottle, and make up to 

 eight ounces with water. I have used this for 

 mounting my plants for the last two or three years, 

 and find that it answers admirably ; but am told 

 that gelatine and water, in which is a little corrosive 

 sublimate has been dissolved, is better (applied hot). 

 — Prosper II. Marsden, Manchester. 



ZOOLOGY. 



Re-Growth of Fins and Scales in Fishes. — 

 In May, this year, one of my children caught a small 

 roach in a brook that serves as an outlet to an over- 

 flow from the park lake. The weather had for a 

 short time previously been very dry, and the brook 

 had but a few inches of water in its deepest parts. 

 The roach was about four inches long, and was 

 sadly injured by the loss of about half his complement 

 of scales and the whole of the dorsal lobe of his 

 caudal fin, his maimed condition being due, probably, 

 to his struggles in the shallower parts of the brook. 

 The fish was caught by hand, and within a few 

 minutes of capture was placed in my aquavivarium, 

 then occupied by three small carp and a loach, 

 innumerable mollusca, &c. In a few weeks the 

 whole of the lost scales were replaced, and a slight 

 fringe occupied the site of the missing portion of the 

 caudal fin. This fringe gradually developed until 

 now (October 6) the late missing lobe is completely 

 replaced, and the fish is the most active in my 

 miniature pond. I may add that my aquavivarium 

 J s only 18 inches square by 8 inches deep, that it is 

 kept on the natural system, and that neither water 

 nor fish have been changed since it was started more 

 than four years since.—/'. C. King. 



Shells from Niagara. — There is a very serious 

 error, involving as it does a totally inaccurate record, 

 in the newly-issued " Proc. of the South London 

 Ent. and Nat. Hist. Soc. for 1887," and as it will be 

 long before it can be corrected in the " Proceedings " 

 for 1888, I venture to ask you to allow me to correct 

 it in your columns. On page 89, I am stated to have 

 sent for exhibition six species of shells from the 

 Niagara River. Somehow, the two notes I wrote 

 for different lots of shells have got mixed up, and of 

 the species mentioned, only Planorbis bicarinains was 

 from Niagara River— all the rest were from Colorado, 

 and the note following about their being also Euro- 

 pean applies only to the Colorado species. Another 

 Colorado species also found in England is Physa 

 hypnorum — I found this near West Cliff this year. — 

 T. D. A. Cocker ell, West Cliff, Colorado. 



Mollusca in Colorado.— During the past sum- 

 mer, Custer county has yielded me a fair number of 



mollusca, including two new varietal forms— Hyalina 

 arborea, var. viridula, shell semi-transparent, greenish- 

 white, and Pupa blandi (Morse), var. alba, shell 

 white — these varieties being exactly analogous to 

 H. alliaria, var. viridula, and P. marginata, var. 

 alba respectively. Both these varieties, like their 

 analogues in Europe, are much more local than the 

 types, although they occur with them. The only 

 snail of any size we have here is Patula Cooperi 

 (Binney), of which the type and var. confluens (bands 

 confluent, giving the appearance of a brown shell 

 with a broad white band above the periphery and a 

 white umbilical region) occur in Custer county. The 

 young of P. Cooperi are keeled, and are remarkable 

 for a feature which seems not previously to have been 

 noticed, namely, that they have numerous fine spiral 

 ridges of epidermis, that on the keel being especially 

 well developed ; in some specimens this condition is 

 so far developed that the shells are beautifully ciliate. 

 — T.D.A. Cocker ell, West Cliff, Colorado. 



The Beauty of the Lichen Mark. — The 

 markings on the wings of moths consist of lines and 

 spots that present a family likeness. Lichens, we 

 presume, came into existence every whit as early as 

 the moth race, and hence it is that the night-moths 

 that sleep on our palings during the sunlight are 

 protected from harm by being patterned to resemble 

 the cushions on, which they repose. There is an 

 amazing adaptability in the moth race ; a chrysalis 

 can secrete a spot of colour so as to vary the wing 

 pattern of the moth it discloses, and during the 

 expansion of the wing membrane a line may become 

 straighter, or more curved lines, may become spots, 

 and spots lines. From such changes we describe 

 species which beget their like. The thinning of the 

 b'rds has left us moths that are lichen-like, since the 

 more they became like the lichens the better chance 

 had they of escape and mating. Sometimes their 

 caterpillars also feed on the lichens, and then, like 

 the marbled beauty {Byrophila perla), a common 

 white fleck on most people's palings, the insect's 

 whole existence is passed at the lichens. Curiously 

 enough this minute moth has a congener, B. glandi- 

 fera, which is only distinguishable from it, in that 

 both itself and its caterpillar more nearly resemble a 

 lichen, but instead of being on that account com- 

 moner in this country, it is scarcer. As I am not 

 aware that the sparrows object to the pearlier dainty, 

 and turn out the greener, bigger, and more question- 

 able affair, in spite of its lichen colour and curves, 

 it is not erroneous to suppose a decrease of lichens 

 and an increasing omnipresence of whitewash and 

 mortar as the plausible explanation. When a school- 

 boy at Bath, I recall making the acquaintance of 

 both these little moths, perla showing up on the grey 

 Bath stones somewhat the earlier. Few fresh lichens 

 now mark the trees of Tyburn and the Fleet, and 

 shed over orchid and primrose tuft the fragrance of 



