HARDWICKE'S SCIENCE-GOSSIP. 



15. 



leaves ; violacca and nigricans have roots which are 

 ■simply fibrous, shorter leaves, and but for the awn and 

 Jhe violet tinge of the panicle and of the leaf sheaths 

 Jiiight pass for forms of ovina. Bouvier lays stress 

 ■upon the branches of the panicle being geminate. 



I may remark also that Avena distichophylla in the 

 ■early stage of its flowering might easily be mistaken 

 Jor siibspicata, if the peculiarity of its leaves be un- 

 observed. 



The descent to the baths is by a steep winding mule- 

 path cut in the face of the precipice. From a ledge, 

 almost inaccessible, we obtained Aronicion scorpioides, 

 and, on debris at the foot of the descent, Galium 

 helveticiim. 



In a meadow farther on. Geranium lividum was 

 met with again. The vegetation about the baths of 

 Leuk has still much of an Alpine character about it, 

 for the height of the place is 4,600 feet above the 

 level of the sea ; and the first indication of being in a 

 country possessing a somewhat different flora to that 

 <jf Berne is the occurrence of the larch, which seems 

 to take the place of the silver fir, so plentiful on the 

 Oberland Alps. 



A good carriage-road leads hence, nine and a half 

 miles, along the Dala Valley to Leuk and Susten in the 

 valley of the Rhone. The following interesting plants 

 were gathered en route : Convallaria verticillata, Coro- 

 fiilla varia, Dianthus atrorubens, Erucastrum Polli- 

 chii^ Erysimum helveticum. Euphorbia Gerardiana, 

 Laserpitium Siler and glabra, Lasiogrostis calama- 

 grosiis, Melica ciliata, Ononis natrix and rotundifoUa, 

 ■Sisyvibriufn austriacum, Stipa pemiata (near Leuk), 

 St'dum reflex um, Thalictrum fcetidum. In the Rhone 

 valley, the Euphorbia above mentioned is the pre- 

 vailing species of the genus : on the Kandersteg side 

 ■of the Gemmi it is E. Cyparissias, which one notes by 

 :lhe roadside among the rocks. Lasiogrostis grows 

 in dense tufts ; the awns are much longer than in 

 Calamagrostis proper, and these with the long silvery 

 hairs at the base of the caryopsis impart a silky 

 ■appearance to the panicle. The cruciferous plants 

 are not easily made out unless in fruit. The 

 Erucastrum might be easily passed over for Sinapis 

 arve7isis. The Sisymbrium may be also mistaken, 

 3)ut in fruit readily recognised by the peculiar torulose 

 character of the pods. Erysimum helveticum has 

 narrow leaves, large petals, and a heavy puberulence, 

 with angular stems and fruits. It is very common in 

 .the Valais. 



{To be continued.) 



ON A METHOD OF PREPARING AND 

 MOUNTING MINUTE BEETLES. 



AFTER trying various materials, I have found 

 that the circles of thin glass used by micro- 

 scopists are most convenient for mounting minute 

 beetles. My experience so far has been confined to 

 a tropical climate, where I was led to discard the 



old paper mounts because every sort of gum used 

 invariably caused discoloration of the card. I now 

 use Canada balsam to fix the insects on the glass 

 and the glass on the small triangular card which 

 receives the pin. The general appearance of the 

 complete mount is shown in Fig. 107. The card 



Fig. 107. 



may be made of suiiScient size to contain any notes of 

 date, locality, &c., that may be considered necessary. 

 The most convenient sizes of glass circles I have 

 found to be ^-inch and j-inch. Small insects can be 

 placed two or more on one circle, larger specimens 

 singly. 



I am accustomed to set the insects before finally 

 mounting them, which allows of their being more 

 neatly arranged. My method is as follows : for 

 "setting-boards" I use thick glass slips, 3 inches by 

 I inch (this size being convenient as fitting into 

 micro-slide cases) ; a small drop of liquid balsam is 

 placed on the glass and spread over a space corre- 

 sponding to the size of the expanded insect ; the 

 beetle is placed in the centre of this patch, and its 

 legs and antenna neatly arranged with a setting 

 needle, the viscid cement holding them in any 

 position in which they may be placed. A large 

 number of insects may be set out side by side on the 

 same piece of glass, and allowed to remain there 

 until sufficiently dry. The limbs of the most minute 

 beetles can be accurately arranged with the aid of a 

 watchmaker's lens or a simple dissecting microscope. 

 After a few days they will be sufficiently stiff to 

 retain their position. The glass slide should then be 

 immersed in a bath of benzine collas, which quickly 

 dissolves the balsam and releases the insects, which 

 rise to the surface of the liquid. They can then be 

 lifted out and placed on blotting-paper to dry. I 

 have never found the benzine to injure even the most 

 delicate colours, nor does it disturb scales and hairs 

 when present on specimens. As soon as the benzine 

 has evaporated the insects are ready for mounting on 

 the thin glass circles; the very smallest touch of 

 balsam is enough to keep them in position. 



This same method is equally applicable to some 

 other classes of insects, such as minute hymenoptera, 

 ants, and hemipteia. I consider the advantages of 

 this system to be — that insects can be more accu- 

 rately set out before being mounted, thus ensuring 

 greater regularity and neatness ; that the under- 

 surfaee of the insect can be readily examined through 

 the glass ; that the previous immersion in benzine 

 acts as a preservative against mites and fungus j that 



