6 PROCEEDINGS OP THE 



The process described above I have hitherto only used with balsam, 

 but certain experiments which I have made lead me to believe that 

 glycerine and gelatine can likewise be employed, and the employment 

 of the latter especially will be an advantage considering how trans- 

 parent balsam renders colourless objects. These two would make 

 the cardboard admirably adapted for mounting Acarides and other 

 minute Arthropods. That it is well adapted for Acarides is shown 

 by the card in the box where we haTe Tegeocranus lotus represented 

 in three stages — the larva and pupa in balsam, and the mature 

 insect gummed outside. 



That objects mounted in this way are readily observed by means 

 of a lens is clear to any one, but it might be objected that high 

 powers cannot be employed for their examination. Such, however, 

 is not the case. For examination under the compound microscope, 

 all that is necessary to do is to place an ordinary glass slide on the 

 stage, then put the card on its upper edge, letting it hang by means 

 of the pin, the lower side of which hangs down. Should the nature 

 of the stage not admit of this, then it is a simple matter to remove 

 the pin out of the card. 



Thus there is no advantage, which the ordinary way of mounting 

 on glass slides possesses, which is not obtained by the use of card- 

 board, while the utility of having the dissection placed alongside 

 the insect, (especially if it be one of use in classification), is suffi- 

 cient to recommend it to the attention of entomologists. ISTor must 

 it be forgotten that cardboard is very much cheaper than glass 

 slides, which cost something like 6/- or 7/- per gross, which is almost 

 saved for the cost of the extra cover glass, and the cardboard will 

 not cost anything like that. 



I may also mention that I have been making some experiments 

 on the lines indicated by Schlectendal, (Ent. Xachr. ), in the way of 

 preserving larvae by the roasting process. After many failures I 

 have succeeded in preserving larvae under 1 inch in length very 

 fairly. The darker colours keep very well, but the lighter greens 

 fade sooner or later; yet, as one or two green larvae have retained 

 their colour, it is possible that with greater experience I may find 

 out the method most favourable to effect this. So far as my 

 experience goes at present, two things are necessary before properly 

 preserved larvae can be obtained — they must be full fed — either 

 ready for pupating, or before they have moulted for the last time 

 when they have the two skins on — and their stomachs must be per- 

 fectly empty. 



