HARDWICKE'S SCIENCE-GOSSIP. 



33 



Dr. Carpenter, iu bis work on the microscope, 

 says that " when the perforation has been made the 

 two blades are separated enough to allow the pas- 

 sage of the eggs between them." 



Mr. Jabez Hogg states " that when the cut is 

 made, the four are drawn together ; and through a 

 central canal which is now formed by combining the 

 whole, an egg is protruded into the fissure made by 

 the saws iu the leaf." Mr. Wood, in " Insects at 

 Home," makes use of this sentence — *"' an egg is 

 then passed between the saws and deposited iu the 

 groove, &c." 



It may seem presumption on my part to question 

 the statements of sucli authorities as are above 

 quoted ; but yet, if we take into consideration the 

 size of the egg and the formation of the saws, it is 

 quite impossible for the process to be accomplished 

 in the manner they describe. The cavity of the 

 body has no outlet through the saws, the bases of 

 which are filled up with the powerful muscles de- 

 stined to move them. The first mention I can find 

 of the saws acting as ovipositors is in an old book 

 on insects, by J. Hill, M.D., published in 1773. He 

 says, in describing the Saw -fly, " The fly is female 

 that is here described; the male has no saw, for he 

 has no use for it. Nature has given that instru- 

 ment to the female, to cut a way into the growing 

 vegetable, and there to lodge the eggs, which pass 

 through the hollow made by the two sides or plates 

 of the saw." 



Figr. 26. Terminal Scgrment under pressure, showing protru- 

 sion of Ovipositor, and the passage of egg through it. 



By soaking a female saw-fly, full of eggs, for a few 

 days in liquor potassse, its skin becomes soft and 

 transparent, and the eggs can be seen lying inside 

 the body. Ey subjecting it to gentle pressure under 

 tlie compressorium, and using a microscope having 

 a low magnifying power, a tube is seen protruded 

 from the end of the abdomen, and along it the eggs 

 can be seen to .travel (fig. 26). This is probably the 

 true ovipositor. 



In the natural position, when not in use. Hie saws 

 are contained in a sheath, situated in a slit at the 

 termination of the body of the insect. Over this is 

 placed a sort of arch, formed by the terminal seg- 

 ment of the body. I'rom this arch springs on each 



side of it an organ resembling an antenna, the use 

 of which is, no doubt, to find the position of the 

 slit made by the saw before an egg is deposited. 

 (See fig. 25.) It is under this arch that the real ovi- 

 positor is protruded. If any of the readers of 

 Science-Gossip have made any observations on the 

 structure of these organs of the Saw-fly, it would 

 be interesting to me to learn the result of their inves- 

 tigations. James W. Gooch. 



A NUT-STOWING BIRD. 



npHE subject of this article is one of my peculiar 

 -^ pets, and a bright, handsome merry fellow he 

 is, with his coat of sober grey and his waistcoat of 

 orange. Ever active, never at rest, ever prying and 

 peeping, he manages at all times to keep his sleek 

 self in a very plump, well-to-do condition. On the 

 mossy trunks of apple and pear trees in neglected 

 orchards he regularly runs riot, and in well-timbered 

 parks his merry twit-twit ! rings out as joyously as 

 the song of the " mounted thrush " or the carol of 

 the "heaven-aspiring" lark. He is essentially a 

 joyous bird. There may be little of music in his 

 simple note, but what there is smacks of genuine- 

 ness, which is more than can be said of many 

 of the trillers and warblers of our own species, 

 whose merry songs often gush from a grief-laden 

 heart. His active and inquisitive disposition is also 

 beyond dispute. All day long he flits from tree to 

 tree, climbs the bole, hangs back — downward from 

 the branches — at the same time peering into every 

 cranny with a perseverance worthy of a higher 

 object than securing a few woodlice, grubs, and 

 beetles. But this is his only object, for hasn't he 

 to keep up his own plumpness, and are there not 

 five or six queer little creatures at home whose 

 well-being and embonpoint depend principally on 

 his success in entomological pursuits ? Accordingly 

 our little friend pecks, taps, twitters, and pries the 

 livelong day. 



But though insects are the staple food of our 

 active little friend, yet at a certain time of the year 

 he becomes, both in principle and practice, a vege- 

 tarian. Into this absurd notion he enters heart 

 and soul. His mania is for nuts, and from this he 

 derives his name, which is Sitta Europaa, the 

 Common Nuthatch — nuthatch, literally rendered, 

 signifying "to chop a nut." At that time of the 

 year when the sun-embrowned clusters of ripe 

 filberts, hazels, and cobs coquettishly peep from the 

 coppice and hedgerow, our little friend wings his 

 way from the park and orchard, and from among 

 the clustering treasures and fading leaves twitters 

 riglit merrily. Selecting one of the finest of the 

 bunch he takes it into his widely-gaping beak, and 

 once more addresses himself to flight. Presently 

 a loud tapping is heard from some quiet corner, and 



