October 22, 1908] 



NA TURE 



655 



There is also a special lever, by means of which the 

 '■ountiiii^ discs can be disengaged and returned rapidly to 

 zero, the lines meanwhile remaining at rest. An important 

 point in the practical working of the instrument is the fact 

 that all mechanism is confined to the observer's post, so 

 that any unskilled assistant can be utilised. 



The instrument is portable, and can be carried by one 

 man even in mountainous districts. 



June 18. — " The Giant Nerve Cells and Fibres of Halla 

 parthenopcia." By Dr. J. H. Ashworth. Communicated 

 by Prof. J. C. Ewart, F.R.S. 



An anterior and a posterior series of giant cells are 

 present in Halla ; the following statement refers to the 

 anterior series. Primary giant cells are formed in seg- 

 ment.'il couples — one couple in each of the anterior ganglia 

 of the nerve cord — until a maximum of eight couples is 

 attained. Secondary giant cells are also formed at the 

 anterior end of the nerve cord, and occasionally in one or 

 more ganglia already possessing a primary couple. There 

 is a progressive increase in the size of the primary giant 

 cells until the worm has attained a length of 30 cm. to 

 40 cm. Yellow granules, probably insoluble products of 

 metabolism, are present in the giant cells. Chromophilous 

 granules occur in great abundance in a specialised peri- 

 nuclear zone, distinguishable in the living cell by its 

 greater refringency. 



The neurofibrillar network in the giant cell is divisible 

 into a peri-nuclear network, situated at the margin of the 

 peri-nuclear zone, and a more extensive, wider meshed, 

 and generally more slender stranded network in the 

 general protoplasm. From this network slender primitive 

 fibrils pass into the cone of origin of the axone, whence 

 stouter fibrils, each due to the fusion of several primitive 

 fibrils, pass into the giant fibre. The bundle of neuro- 

 fibrillar occupies from one-fourtli to three-fourths of the 

 internal diameter of the giant fibre. 



The anterior giant cells of Aglaiiridcs fulgicia agree in 

 the main features of their arrangement and structure with 

 those of Halla. 



Entomological Society, October 7. — Mr. C. O. Waier- 

 house, president, in the chair. — Exhibits. — W. G. 

 Sheldon : Butterflies from Andalusia taken in the spring 

 of this year. They included Anthocharis belcinia and var. 

 glauce ; .4. tagis, low-level and high-level forms ; Zegris 

 euphcmc, var. meYtdionalis ; Melitaca phocbe, var. 

 occitanica ; A/. deionCy a very large and well-marked form ; 

 and Melanargia ines with one striking aberration show- 

 ing a strong melanic tendency. — Dr. Herbert Charles : 

 Remarkable aberration of Dryas paphia, taken in the 

 New Forest in July. With the exception of the borders 

 and the bars, all the upper 'sides of the wings were 

 suffused with deep velvety-brown triangular patches, the 

 maculations being entirely absorbed therein. — Hugh 

 Main : living larv^ of Blatta gerinanica to illustrate their 

 colourless condition on first emergence. — H. St. J. Donis- 

 thorpe : Examples of (a) Agrilus higuttatus, ¥., from 

 Sherwood Forest, not taken in Britain for about thirty 

 years ; (b) Pyropterus affitiis, not uncommon in Sherwood 

 Forest, July ; (c) a species of Phora, with pupae bred from 

 larvae which came out of the body of a Clems fortnicarius 

 taken alive in Sherwood Forest, July, with the Agrilus, 

 and probably parasitic on it; (d) Trogolinus anglicatiKS, 

 Shp., a specimen taken at Bembridge, August 3, with 

 a specimen from Plymouth, only known before to occur 

 in New Zealand and at Plymouth ; (e) Phytn niclano- 

 cephala, Mg., bred from wood-lice taken at Bembridge, 

 Isle of Wight, August, with pupse, and a wood-louse with 

 dipterous pupa in situ. The life-history of the fly was 

 hitherto unknown, though the larvae of Rhiiiophora aira- 

 tnentaria, Mg., a nearly related species, have been recorded 

 as parasitic on Oniscus asellus. — .\. Harrison : A 

 gynandromorphous example of Pieris napi, bred from 

 parents taken in north Cornwall this year. — E. R. 

 Speyer : Rare and interesting dragon-flies taken in the 

 British Isles in 1908, including Sympetrmn jonscolomhii, 

 -Selys, cJ and 9i taken in Hertfordshire on June 24 and 

 July 27 respectively; SomatochJora metallica. Lind., a d 

 captured in Sussex on August 4, being the first authentic 

 record of this insect in England; and Libellula qiiadri- 

 tvaciilnta, Linn., four specimens, showing the remark.Tble 



NO. 20,34, VOL. 78] 



difference in the amount of suffusion on the wings in 

 individuals. — Norman Joy : Examples of Coleoptera new 

 to the British list. — H. M. Edeisten : Specimens of 

 Aeschna isosceles and Libelhda fiilva from Norfolk 

 Broads, taken in June, and Orihctrum cacrulescens from 

 Chagford, taken in July. — W. J. Lucas : A spike of the 

 grass Moliiiia cacrulea with dead Syrphids, Melanostoma 

 scalare, Fabr., attacked by the parasitic fungus Empusa 

 mitscae, found on Esher Common, October 3. Many or 

 most were attached by the point of the head only in a 

 very peculiar manner, and apparently all were females. — 

 O. E. Janson : A specimen of Cryptaniorpha desjardinsi, 

 Gu^r., found by Mr. F. C. Selous at Barton-on-Sea, 

 Hants. This beetle is recorded as living on banana plants 

 m Mauritius and Madeira, and may have been introduced 

 liere in the banana fruit. — W. West : Specimens of the 

 following insects : — Aleochara crassiuscula, Sahib., taken 

 at Great Yarmouth in May; varieties of Donacia dentipes 

 and D. sitnple.x, from Caistor Marshes ; Nabis boops, 

 Schiodte, taken at Esher in August ; and Idiocerus scurra. 

 Germ., taken at Blackheath, Kent, in September. — L. W. 

 Newman : Specimens of (o) Crymodes exulis from the 

 Shetlands, including one of the very rare female ; (6) Calli- 

 morpha dominula, two yellow aberrations bred from east 

 Kent ova ; and (_c) a varied series of Camptogramma 

 fluviata. — Dr. F. A. Dixey : .\ number of Central and 

 South American butterflies belonging to six different sub- 

 families, but all showing the same obvious character of a 

 diagonal reddish band on a general dark surface. — Papers. 

 — Bionomics of butterflies : Dr. G. B. Longrstaff. — Some 

 additions to the Perlidas, Neuroptera-Planipennia, and 

 Trichoptera of New Zealand : L. J. Hare. — The larvae of 

 Hamanumida daedalus, Fab., Hoplitis phyllocampa, n.sp., 

 and Stilophonotus myrineleon, Feld, with descriptions of 

 the imagines of the two Heterocera : Roland Trimen. — 

 Revision of the Australian and Tasmanian Malaco- 

 dermida; : A. M. Lea. 



Institution of Mining and Metallurgy, October 15. — 

 Mr. Alfred James, president, in the chair. — The separa- 

 tion of metallic ores by jigging : A. Taylor. A descrip- 

 tion of a modification of the ordinary mechanical jig, 

 devised by the author, in which a vibrator is substituted 

 for the usual plunger. The vibrator consists of a shaft 

 provided with discs or fly-wheels so constructed that their 

 centres of gravity do not coincide with that of the shaft 

 to which the hutch is attached ; consequently the revolu- 

 tion of the shaft and hutch carrying the screen, in accord- 

 ance with the law which compels a rapidly revolving mass 

 to rotate around its centre of gravity when uncontrolled 

 by fixed bearings. In this case the whole apparatus is 

 hung on springs, allowing of free vibration in any direc- 

 tion. The paper containu also a description of the ores 

 for the special treatmcni of which the apparatus was 

 primarily designed. — Laboratory routine in modern 

 smelters': H. T. Waller. A brief description of methods 

 found useful by the author in connection with copper blast- 

 furnace smelting. These include the analyses of slags and 

 matte, and determinations of copper, iron, silica, lime, 

 aluminium oxide, zinc, and sulphur. — Reinforced concrete 

 foundations for stamp batteries : S. J. Truseott and 

 J. P. Fuller. A detailed account of the replacement of 

 the original wooden mortar blocks of the stamp battery 

 at Rediang Lebong, Sumatra, by others constructed of re- 

 inforced concrete, with notes on the composition of the 

 materials used and the cost of the work. — The estimation 

 of sulpho- and ferrocyanides, &c., in cyanide solutions 

 containing copper : L. M. Green. This paper deals with 

 the complications arising from the presence of copper in 

 solutions obtained in the cyanide treatment of silver and 

 gold ores in regard to the determination of sulpho- and 

 ferrocyanides. Cupric and cuprous double cyanides 

 exercise a reducing action on permanganate in acid solu- 

 tion, and precipitate both sulpho- and ferrocyanides, so 

 that an ordinary method of determination is often 

 impossible. The paper describes some of the reactions and 

 tests to be adopted iji these circumstances. — Mine 

 sampling devices : H. E. Hooper. Two devices, a hang- 

 ing sampling chair for use in winzes, and a catching bag 

 for employment in conjunction with the chair, are here 

 bricfl\- described and illustrated. 



