SCIENCE-GOSS/I'. 



119 



of the best travelling microscopes we have soen. 

 The price of the stand, with one eye-piece ami the 

 necessary case, hut without objectives or other 

 apparatus, is £5. 



Royal .Microscopical Society. — A1 the meet- 

 ing on June 20th, the President, Mr. Carruthers, 

 F.R.S., in the chair, Mr. C. H. J. Rogers exhibited 

 a modification of the Ronsselel compressor, in wliich 

 two thin india-rubber bands, sunk into grooves, 

 were employed to keep the cover-glass in position. 

 The advantage of this modification is the facility 

 with which a broken cover-glass can he replaced. 

 Mr. Chas. Baker exhibited an acromatic substage 

 condenser which was a modification of Zeiss's model 

 of the Abbe condenser, the X.A. being J •(), aplanatie 

 cone '.10°, lenses —-inch diameter, working distance 

 A inch. With the front lens removed the con- 

 denser is suitable for use with low-power objectives. 

 A short paper by Mr. E. B. Stringer on a new pro- 

 jection eyepiece and an improved polarising eye- 

 piece was taken as read. Miss Loraine Smith 

 contributed a paper on some new microscopic fungi. 

 and Mr. Bennett in commenting thereon referred 

 to the proposed cultivation of fungus parasites on 

 certain insects, especially on the Continent and in 

 Australia and America, with a view of getting rid 

 of insect pests, locusts, and others. The President 

 then read a paper, and gave a lantern demonstra- 

 tion on the structure of some palaeozoic plants. 



EXTRACTS FROM POSTAL MICROSCOPICAL 

 SOCIETY'S NOTE-BOOKS. 



[In accordance with the announcement in our 

 last issue we commence the publication of extracts 

 from the note-books of the Postal Microscopical 

 Society. Beyond absolutely necessary editorial 

 revision these are printed as written by the various 

 members, without alteration or amendment. Cor- 

 respondence on these notes will be welcomed. — 

 Ed. Microscopy, S.-G.] 



Scalp: from Leaf of Lemox-tree. — The scale 

 insects, Coccidae, members of the order Hemiptera, 

 sub-order Homoptera, belong to that division of 

 the sub-order which is distinguished by having 

 only one joint on the tarsus. (') The females are 

 common on many plants, and are found both on 

 leaves and bark. They appear as small, brown, 

 waxy, convex lumps, more or less elliptical according 

 to species. If the brown case be lifted, one sees a 

 small fleshy mass, with eggs, and usually a cottony 

 substance. The fleshy mass is the female, which 

 dies as soon as the eggs are laid. The eggs hatch 

 into a small, active larval insect with eyes, legs, 

 antennae, and a sucking mouth. After a time these 

 insects fix themselves to a leaf or the bark by 

 means of their sucker. If they are to become 

 females they excrete the waxy shell, throw off all 

 legs and processes, lay their vis<j;s. and die. If they 

 are to develop into males, they draw in their legs 

 and become chrysalids, with a process on each side 

 containing the future wings. The adult males are 

 seldom seen. The male and larva are figured in 

 Miss Ormerod's book. A friend of mine is now 

 trying by an ingenious contrivance to obtain speci- 

 mens of the males and larvae. He has run the 

 branch of a rose tree, not cut off, into a lamp 

 chimney, and packed the ends with cotton wool. 

 He thinks that when the scale eggs on the branch 

 (1) Query— apparent joint ?— [Ed. Micro?.] 



hatch out he will find the Larvae inside the glass. 

 The second slide shows a scale in which a parasite, 

 probably an ichneumon fly, h;e- laid its egg, and 

 the grub has hatched and eaten all the Seal 



The grub is shown lying by the side of the scale. 

 The scales thus attacked are usually of a lighter 

 colour 1 ban the rest. 

 Sheep-tick Imago. -A tick is a degenerate fly 



that has lost its wings. (-) The sheep-1 Lck passes t he 

 larval state inside the body of the mother. The 

 pupae may be found in little brown shiny cases 

 about three millimetres in diameter. If these are 

 broken open the Eully formed tick is seen inside. 

 The>e are better adapted for mounting than the 





S> 



Sheep-tick. 



adult insect which has already sucked blood. The 

 spiracles should be noticed, especially the thoracic 

 ones ; also the toothed claws and the tree-like 

 formation between them, answering to the pad on 

 the foot of the house-fly. 



Aphis with Young. — The peculiarity in this 

 slide is that the winged female in November ought 

 by all rules to be oviparous. The fact of this one 

 being viviparous at that time of year shows how 

 circumstances modify natural habits. The chrys- 

 anthemum from which this aphis was taken was in 

 a greenhouse ; had it been in the open air the aphis 

 would have laid egsrs — at least, if entomologists 

 are to be believed. In the slide showing the pupal 

 aphis the wings are still seen confined in their 

 cases. Both larval and pupal aphides produce 

 young; a phenomenon known as Poedogenesis. 

 Aphides during the summer are viviparous and 

 produce their young parthenogetically. In the 

 autumn the union of the sexes takes place and the 

 result is, not living young, but egs:^. The spi 

 of aphides are very numerous. The aphis which 

 spins the wool on apple trees has do cornicles. 

 Aphides, like Coccidae, are of the order Hemiptera, 

 and sub-order Homoptera, but belong to that divi- 

 sion of the sub-order which has two joints on the 

 tarsus (Dimerae). 



(2) The "sheep-tick" here alluded to b Melophagus ovinus, 

 belonging to the family Hippoboscidae, order Diptera. The 

 ticks proper belong, of course, to the Acari, and come undi 

 head of Arachnida, Ixodes reduvius 1 \'^i- S.-G., Vol. VI., n.s., 

 p. 5) is also known as •• the sheep-tick." [Ed. Micros.] 



