HARDWICKE'S SCIENCE-GOSSIP. 



261 



BOTANY. 



Primroses.— During the early part of this spring, 

 wliilst phicking primroses, I observed what I 

 consider an apparent contradiction to the two 

 distinctly defined varieties. Off one root I obtained 

 flowers of both kinds. There were two whose 

 androecium was above the gynoecium to three of the 

 opposite arrangement. Subsequently, in the hundreds 

 of plants I examined, I was unable to find a 

 repetition. Has this before been noticed? I have 

 been unable to find any note of it elsewhere ?— 

 G. F. G. 



Paris quadrifolia.— In answer to Mr. Colwall's 

 inquiry as to the variation of this plant, I can inform 

 him that the number of the leaves is by no means 

 constant. Herb Paris is frequent in this neighbour- 

 hood, and has five leaves almost as often as four, 

 and I have gathered it this year with six, or even 

 seven leaves. — C. W. Greenwood, Frox field, Petersficld. 



Paris quadrifolia. — It may interest K. D. 

 and others to know, that my sister has this season 

 collected a large number of specimens of this plant 

 with varying numbers of leaves. In a large clump of 

 it growing at Rudden Brow, near Goosnargh, the 

 number of specimens with three, five, six, and, in 

 one instance seven leaves, considerably exceeded 

 those with the usual four. I may state that this 

 particular group of plants was remarkably luxuriant 

 in growth, the situation seeming to agree well with 

 them. — R. Stauden. 



Saxifraga iiirculus. — The note at p. 239 of the 

 re-discovery of the rare Saxifraga liirailus in co. 

 Antrim is not the first record of that interesting fact, 

 and S. A. Brennan is only second among the happy 

 finders. J. L. Praeger found it on the 8th of July on 

 the headlands north of Cairnlough in co. Antrim in 

 abundance and in beautiful bloom, and the fact was 

 mentioned in the account of the "long summer 

 excursion of the Belfast Naturalists' Field Club " 

 which appeared in three Belfast newspapers on the 

 17th July. I could particularise the exact spot in 

 which this treasure flourishes, but neither Mr. Praeger, 

 nor any other botanist would wish to have it visited 

 by the plant exterminators whose ravages are 

 unfortunately extending even to Ireland. In Mackay's 

 "Flora Hibernica" is the remark — "It is singular 

 that this plant, which Dr. Hooker found in Iceland, 

 should not be found in the north of Ireland." — 

 //. IV. Lett, M.A. 



^ To Skeletonise Leaves. — May I add a post- 

 script to Mr. Crombleholme's note on this subject on 

 page 238. The best time to gather the leaves is from 

 the third week in June to the fourth week in July — 

 just when the foliage is in perfection, and before it 

 begins to get too dry and woody. When the leaves 



have been skeletonised they may be bleached to 

 an almost pure white by being immersed in a 

 bath of dilute chlorine ; the older the leaf, the 

 stronger the solution required. They must be 

 watched in the bath, and carefully removed as soon as 

 bleached, then washed in clean cold water and laid 

 out to dry on clean blotting-paper. They may, when 

 dry, be tastefully arranged on a stand. This will be 

 found a pleasant occupation for the winter evenings. 

 It may also be mentioned that photographic views 

 of these groups form some of the most charming 

 stereoscopic pictures. — C. Beak, Roivley Regis. 



GEOLOGY, &c. 



Incrustation in a Water-pipe, — At the Inker- 

 man coal-pit number one, Renfrewshire, a wooden 

 water-pipe, which had been in use for upwards of 

 twenty-four years for carrying water, gave occasion for 

 examination, which, on being opened, was found to be 

 nearly filled with an incrustation which the miners 

 called an "incrustation of salt." The incrustation 

 when removed from the pipe was dark gray or slate 

 coloured, hard, and rock-like, and the pipe in which 

 it was formed being square the incrustation measured 

 outside 2 1 J. X 2 Ij! in., and which is the original size 

 of the pipe, but by it was reduced to a square hole 

 measuring only j| X |g in., which is in the centre of 

 the incrustation, while the walls of the incrustation 

 measure in thickness |^, \\, j|, \% in. From each of 

 the corners to the corners of hole in the centre are 

 lines of cleavage. This form of incrustation is 

 common in limestone districts, and affords a good 

 example of rock formation. I analysed a sample of 

 the above incrustation and found : 



Carbonate of lime 



(Jangue (i.e., mud or clay) 

 Hydrated peroxide of iron 



77'SO 

 io*oo 



2-50 



lOO'OO 



from which it will be seen that carbonate of lime is 

 chief in the deposit. The rock thus formed is called 

 Travertine, as it is compact, hard and semi-crystalline 

 which distinguishes it from a similar deposit, viz., 

 calc-tuff or tufa, which is loose and porous. — Taylor, 

 Siib-eurator, Museicm, Paisley. 



Large Unios. — Last July, the artificial lake, near 

 the hall at Ossington, having been drained for the 

 purpose of removing a deep deposit of mud, I found 

 a number of the finest specimens of Unio pietorum I 

 have ever seen. The largest measured 4{| inches in 

 length. I las this been exceeded ? I obtained as many 

 as the soft mud allowed me to reach, the remainder 

 have since been taken away with the material removed 

 ' by the workmen. — U\ Gain Tiixford. 



