54 



HATLDWICKE'S SCIENCE-GOSSIP. 



[March 1, 1867. 



Podurre ? " The question was soon settled in the 

 affirmative after the examination had been made 

 under the microscope of two or three captured 

 specimens. The scales were, however, smaller and 

 more transparent than those on my bought slide, 

 and the markings far less distinct. Having paid 

 some attention to these insects since then, I proceed 

 to record my notes. 



With regard to the habits of Podurae, and the 

 places where they may be successfully sought, I 

 may say they all love damp situations. Some pre- 

 fer an excessively moist condition, such as the sur- 

 face of a puddle in the open country or by the road- 

 side. These are destitute of scales, and sometimes 

 occur of considerable size. (See figure in "The 

 Micrographic Dictionary," page 554.) They may 

 also be found under stones in damp places, and 

 often are abundant at the edges of weedy ponds. 

 Others are content with the humid atmosphere 

 under the broad leaves of a dock, or at the roots of 

 a dandelion ; and others again show their aversion 

 to daylight by taking up their abode under a stone, 

 or amid the cobwebs and the darkness of a damp 

 cellar. In these latter localities more particularly 

 do the scale-bearing species delight. 



They feed upon decaying animal and vegetable 

 substances, such as a stale cooked potato, decaying 

 leaves or vegetables, a rotten bone or an egg-shell. 

 All these form capital baits. In addition I find 

 oatmeal is moderately successful in a cellar, and an 

 old shoe has been recommended to us as possessing 

 special attractions. The easiest mode of capturing 

 Podurae, when found, is one told me by Mr. Powell, 

 the eminent optician. A small glass tube a quarter 

 of an inch in diameter, and about two inches long 

 (a quill will do nearly as well), open at one end and 

 corked at the other, is placed over the insect, which 

 most probably takes a leap into it instantly. The 

 open end can then be closed, and you have your 

 prisoner safe. In order to obtain the scales I ad- 

 minister chloroform vapour, and then, with the side 

 of a needle, press the Podura gently on the thin glass 

 cover, which has been previously cleaned. I some- 

 times find they leap into the glass tube so violently 

 as to die on the spot from their self-inflicted injuries. 



The Podura belongs to the order Thysanura, the 

 characteristics of which, as extracted from the 

 " Micrographic Dictionary," are as follows :— 

 "Wings absent; not undergoing metamorphosis; 

 not parasitic ; mouth furnished with mandibles and 

 maxillaj ; eyes simple, in two groups; abdomen 

 mostly terminated by setse or a bifid tail." 



The Podura possesses about sixteen simple eyes, 

 arranged in two groups, one on each side of the 

 head. Each group, containing eight, looks like a 

 cluster of beads.* 



The forked tail is not less curious in its structure 

 than in the use to which it is applied. When at 

 rest it is kept in a groove under the abdomen, but 

 it is brought into operation very effectively in case 

 of danger threatening its possessor. If the alarmed 



* It would appear that some species have 14 or only 12 eyes : 

 there is often much difficulty in counting them. 



Fig. 3S. Tail of Podura, expanded, x 40. 



insect finds its legs cannot carry it into safe quarters 

 quickly enough, it suddenly straightens out its tail 

 horizontally, thus striking a smart blow with it on 

 the ground. The force of the blow is sometimes so 

 great as to cause the creature to rise into the air 

 some twelve inches or so, and then it alights in an 

 unexpected place, whence it crawls away in security. 

 I think a curious orgau (situated between the third 

 pair of legs), which I also saw, on one occasion, used 

 as a sucker, when the Podura was walking in an in- 

 verted position on the under-side of the cell-cover, 

 assists the tail in the operation. The whole appa- 

 ratus bears some resemblance to the ingeniously 

 contrived wooden toy frog, which, by means of a 

 string, a piece of wood, and a bit of cobbler's wax, 

 can be made to leap for the amusement of children. 

 The antennae are four-jointed, and the whole body 

 is covered with a series of scales arranged very 

 much after the fashion of those on the wings of 

 moths. The antennae, as well as the legs, which 

 terminate in two claws or toes, are clothed with 

 fine hairs, and also in some cases with scales. 



My experience refers especially to two kinds of 

 scale-bearing Podurae ; oue of them black or leaden- 

 coloured (P. plumbea ?), and another of a fawn- 

 colour, somewhat speckled. I shall speak of it as 

 the Speckled Podura, for want of knowing its scien- 

 tific name. I do not think it has been described ; 

 its scale certainly has not, and I shall allude to it 

 presently. The former is of frequent occurrence 

 under some boards at the back of our house, and 

 also in similar situations in a cellar at Brixton ; the 

 latter occurs in the same cellar, but inhabits the 

 woodwork and the whitewashed wall, rarely being 



