T. CURTIES AND J. E. INGPEN ON INSECT MOUNTING. 231 



which treatment thej were preserved in the most perfect manner, 

 with total absence of the usual milkiness, and with the various 

 parts in their natural positions. Good examples of this method 

 were in the collection; among them such objects as aphides in 

 various stages of development, on a leaf; a scale-bearing Psocus 

 (an insect of great interest) ; small spiders ; the eggs, larva, j^upa, 

 and imago of gnats, together on one slide; &c. Larger insects, 

 after being killed in ether, were placed for four or five days to dry 

 between the leaves of a book, with a light piressure, after which 

 they were immersed in spirit of turpentine until all the watery 

 matter was extracted, and then mounted in a very thick film of 

 Canada balsam, which was exposed to the sun until hardened. By 

 this method, the natural forms of the insects were but little if at 

 all altered, and some of the specimens showed eyes, antenna?, 

 trachea?, and ovipositors most satisfactorily. Generally, care had 

 been taken (contrary to the usual custom) to attain as little trans- 

 parency as possible, under the idea that the less natural appearances 

 were altered the better. Many of the preparations polarized well, 

 owing to the fact that the muscles were left entire, and not injured 

 by soaking in potash. In some of the letters from Mr. Green which 

 were read, special reference was made to the fact that the natural 

 appearance and characteristics of the insects were really preserved 

 by the methods used. Possibly, part of the success was due to 

 the peculiar action of a tropical sun, which might, perhaps, exer- 

 cise a greater effect in preserving the parts in a natural state than 

 could be obtained by artificial heat alone. The balsam also seemed 

 somewhat dissimilar from that now used in England, and from its 

 yellowness and toughness, more nearly resembled that employed in 

 the early days of microscopy. The objects were presented to the 

 Club rather as specimens of the successful mounting and preser- 

 vation of insect structure than as an entomological collection, but, 

 as some of them had been named by Professor Westwood and 

 others, they became of additional value to the cabinet of the Club. 

 With regard to the transmission and preservation of rare and 

 minute tropical insects, Mr. Green's plan seemed to possess great 

 advantages over dry mounting on cards or immersion in alcohol — 

 in fact, specimens could not be kept in the tropics dry for any 

 length of time on account of the white ants, and when sent in 

 alcohol were almost always injured. The objects presented to the 

 Club were in exactly the same state as that in which they were 



