I02 



NA TURE 



[December i, 1892 



British Earthworms. 



I ENTIRELY Concur with Dr. Hurst's view that the supposed 

 new pecies, de^^cribed by the Kev. Hilderic Friend as L. ru- 

 bescens is in reality Savigny's L.fr'siivus. I may add a further 

 reason for discarding the termZ. terrestris, Lin., and substituting 

 L. herculeus, 8av., for our common large worm. Savigny himself 

 used " Enterion terrestre" to indicate a worm diflfmng consid- 

 erably from L. tei-restris, Lin., in the position and extent of the 

 clitellum ; moreover it belongs to the genus Allolobophora and not 

 to Lunibrictis at all. 



With regard to the second "new" species, A. cambrica, 

 recently de-crited by Mr. Friend, I believe that it is merely a 

 variety of A. chlorotica, Sav. 



Acconling to the description it appears to differ from the latter 

 species in three points: — (l) colour; (2) extent of clitellum ; 

 (3) number of spermathecae. 



(1) Now, anoiigst my collection of British worms I find one, 

 of which a water colour sketch taken from the living specimen 

 closelv resembles Mr. Friend's description of the colour of A. 

 cambrica. My notes as to size, habits, &c., agree with his 

 description. I have carefully re-examined my specimen, and 

 find that it agrees perfectly with A. chlorotica ; or, in other words, 

 I find that A. chlorotica may vary — as Hoffmeister knew that it 

 did vary — so much as to resemble A. mucosa, and I may suggest 

 that it is a mimetic resemblance. 



(2) Further, with regard to the clitellum of A. chlot'otica ; in 

 the table given by the Rev. Hilderic Friend, it is stated to cover 

 somites 29-36. As a matter of fact the next somite, 37, is 

 nearly always included. This brings A. cambrica. Friend, into 

 harmony with A. chlorotica, Sav. 



(3) Thus the only differential character left is the number of 

 spermathecse ; and I cannot agree to the validity of a new 

 species on this single character ; several specimens should be 

 examined to settle the point, as variation in this feature is known 

 to occur. 



I take a certain amount of credit to myself for the useful 

 faunistic studies on the earthworms of Great Britain, now being 

 pur-ued by the Rev. Hilderic Friend, for, if I mistake not, I 

 put him in the way of recognizing their specific characters, 

 when, some years ago, I named for him, with remarks thereon, 

 sundry consignments of some scores of worms which he sent to 

 me f )r that purpose. Wm. Blaxland Ben ham. 



The Dept. of Comparative Anatomy, Oxford, 

 November 21. 



Egyptian Figs. 

 The accompanying sketch represents an instrument used in 

 Egypt for removing the " eye" or top of the sycomore fig. It 

 is a piece of hoop iron, blunt on one edge and tolerably sharp 

 on the other, and fixed into the end of a stick. The fruit of 

 Ficus sycomorus, or " Egyotian fig," seems to be invariably 

 infested with the insect Sycophaga crassipes, Westw. ; which I 

 am informed by Rev. T. F. Marshall, who has kindly given me 

 the name, is the same insect supposed to effect caprification in 

 Malta, ju'iging from specimens wnich I sent him. This fig never 

 produces ripe seed in Egypt, though it has been introduced 

 from the earl est times. Not only are the ancient coffins made 

 of the wood, but it was adopted as the sacred " Tree of Life. 



It probably came from Yemen, where Dr. Schweinfurth saw 

 many seedling trees growing spontaneously. The tree bears 

 three crops per annum, in May, June, and August — Septem- 

 ber. Boys cut off the top of the figs of the first two crops only. 

 Dr. E. Sickenberger, one of the professors in the School of 

 Medicine, Cairo, informs me that the figs have no pleasant 

 flavour until the operation has been performed: — "They then 

 become very s veet, but remain smaller than when not cut open. 

 The object is to let the insects escape. Those that are left 

 become watery and tasteless, and are full of namoos or svco- 

 phaga." In his first description Dr. Sickenberger described 

 the instrument as "a kind of thimble made of iron plate 



NO. 1205, VOL. 47] 



ending in a spatula like a finger-nail. It is fixed on the thumb- 

 of the right hand. The operai ion is only made on fruits which shall 

 be picked up the following day. The day after the operation the 

 fig is quite ripe. The male flowers in those figs are all aborted, 

 and the females have never perfect seeds. The figs of the third 

 generation are larger, of an agreeable taste, and sweet-scented ;. 

 but they are not operated upon, only because in August and 

 September, though the trees are much fuller of fruit than in 

 May and June, the people have so much to do at that time. 

 They are seldom sold, and only eaten by the owners of the 

 trees, or else they are abandoned to the field-mice, birds, and 

 dogs, which latter are very fond of them. These nilg fruits are 

 full of sycophaga." 



It will be seen that the instrument he has sent me is of a 

 different shape to the one he describes ; and the chief interest 

 lies in the fact that Pliny also describes the process as clobely 

 corresponding with this modern method. He even uses a similar 

 term " nail" (ovvxo-s) : Trfirreiv ov Svvarai tiv fxii iirtKvtcrd^- iiW 

 <lXovres 6vvxa'!: fftSripovs itriKvi^ovaiv & S' h,v firiKViffO^, reTdpraia 

 TTeiTTfTai (Nat. Hist. xiii. 14). Further, the Prophet Amos 

 describes himself as bolds siqmtm ; and the authors of the LXX, 

 writing in Alexandria, appear to have understood the expression 

 and translated these word-> by kvi^wv crvK&fiiva. This is the same 

 verb as that which Pliny uses ; so that it would seem to be pretty 

 certain that Amos performed identically the same operation on the 

 figs as is still done in Egypt at this day. It will be noticed that 

 the idea was to ripen the figs. It does not really do this, 

 because there are no seeds ; but it does make the fig 

 sweeter. It also liberates the insects, and without doing this- 

 the fi^s would be uneatable. Jerome is the only author, as far 

 as I know, who alludes to " grubs " being inside the fig. 



George Henslow. 



Iridescent Colours. 



The article "Iridescent Colours" on p. 92 puts me ii> 

 mind of a notice which I published thirty years ago, while I 

 lived in the United States. It was entitled " Harmonies of 

 Form and Colour " {Stettiner Entom. Zeitung, 1862, pp. 

 412-414), and a portion of it refers to the subject of the 

 above-mentioned article in Nature, and may be of interest to- 

 ils readers : — 



" A fundamental observation, which proves the influence of 

 the intensity of light upon colour, may be made on some insects 

 of metallic coloration, inhabiting a large area from north ta 

 south. About six years ago, while in Southern Russia, I took 

 a walk during sunset, and was struck by the brilliancy of some 

 metallic red Chrysomelee, abundant in that locality. I found 

 that it was the common C. fastuosa, which I did not recognize 

 at once, because in the environs of St, Petersburg, where 

 I lived at that time, it occurs in its metallic-green variety, with 

 an iridescent blue stripe on each of the elytra. Still farther 

 north it assumes a more violet metallic colour. The same is 

 the case with Chrysomela cerealis and C. graminis. The first 

 of these species is represented in St. Petersburgh in the blue 

 variety (C. ornata, Ahrens), while the typical variety, occurring 

 farther south, has purplish-red metallic stripes. It is evident 

 therefore that the metallic colouring of these wide-spread 

 species is gradually intensified from north to south, in the order 

 of the colours of the spectrum. We may imagine the area 

 which these beetles occupy, like an immense rainbow, reflected 

 from their backs, violet in the north, red in the south ; the 

 violet perhaps connected in some way with the magnetic pheno- 

 mena prevailing in the polar regions. The longicorn beetle 

 (Callidium violaceum) nndergoes the same variation: violet in 

 the north, blue in central Europe." C. R. Osten Sacken. 

 Heidelberg, Germany, November 27. 



The Afterglow. 



There has been for three weeks past a very remarkable re- 

 newal of the afterglow. There is a quite deep secondary red 

 glow after the stars are fully out. I should say that no such 

 afterglow has been seen since 1886, or three years after the 

 Krakatab eruption. There is also a great extension of the white 

 hazy atmospheric corona around the sun, very marked also 

 around the moon. I am unable, however, to make out any of 

 the pink colour on the outer edge of the haze, which was so char- 



