November 2, 191 1] 



NATURE 



27 



against that of Bates. There were also acraeine mimics 

 which mimicked other species of the same family, them- 

 selves mimics of the primary acraeine models. The rest 

 of the exhibit was concerned with examples from Lagos, 

 among which was a caterpillar of a well-known moth 

 (Nyctemera), which before becommg a chrysalis secreted 

 and covered itself with a mass of bubbly froth, which on 

 hardening resembled the cocoons of a braconid parasite, 

 and probabl}' acted as a protection against insectivorous 

 birds or lizards. 



The Scent Patches of Lepidoptera. 



Dr. F. A. Dixey described the scent patches of certain 

 butterflies and their associated tracheae. The males of 

 many butterflies possess the power of emitting a scent, 

 which is apparently attractive to the female. The scent 

 patches are best distributed in Pierin^ (.e.g. the orange 

 tip). The apparatus consists of specialised scales scattered 

 over the upper surface of the wing of the male. The scent 

 is elaborated by cells in the wing membrane ; the oil enters 

 the specialised scale at its basal foot-stalk, and escapes by 

 fimbria; at the distal end of the scale. In other cases 

 (e.g. the clouded yellow) the scent scales are aggregated 

 into patches, so arranged that, in the ordinary position of 

 rest, the patches of the fore- and hind-wings are coincident. 

 The scales of these patches have neither foot-stalk nor 

 fimbrice. In some species of Catopsilia there are two 

 specialised scale patches, which Dr. Dixey found to be 

 provided with a special tracheal supply derived from the 

 larger tubes in the wing veins. On reaching the scent 

 patch the main tracheal trunks were found to break up 

 into branches, the ultimate distribution of which was not 

 ascertained, but appeared to bear a definite relation to the 

 scent scales. Dr. Dixey suggested that the tracheae were 

 concerned in the dispersion of the perfume through the 

 scales, acting in the manner of a vis a tergo. 



The Biology of Eels. 



Dr. Jobs. Schmidt (Copenhagen) gave an account of five 

 years' Danish investigations on the biology of eels. These 

 have shown that the biology and reproduction of the conger 

 and eel are more complicated matters than they seemed 

 after the publication of Grassi's work. In the case of the 

 eel, the youngest stages found are 4 cm. in length, and it 

 is therefore not yet possible to state exactly where in the 

 Atlantic the eel spawns, except that it must be outside the 

 continental slope. All the larval stages, even the youngest 

 (but not the eggs), of the conger are known, and it can 

 now be stated that the conger spawns everywhere in the 

 Mediterranean and in the Atlantic west of Gibraltar ; 

 how far west is not yet ascertained, but the half-grown 

 larvae of Conger vulgaris have been taken near the Azores. 

 These investigations have not confirmed the earlier suppo- 

 sitions (of Grassi) that the larval development of eels takes 

 place at_ the bottom of the sea or in great depths. All the 

 muraenoid eggs (several thousands) were taken near the 

 surface of the sea, as were also the youngest pre-lepto- 

 cephalic stages, e.g. of Conger vulgaris and C. mystax. 

 The full-grown larvae of the eel and conger also occurred 

 in the upper layers. Muraenoid eggs were found not only 

 in the Mediterranean, but also right across the Atlantic 

 between 20° and 40° N. lat. Evidently, therefore, some 

 eels spavirn there, but how far from the surface has not 

 yet been ascertained. Dr. Schmidt illustrated his remarks 

 by charts and a beautiful series of larval and meta- 

 morphosing examples of several species. 



The Dorsal Vibratile Organ of the Rochling (Motella). 



The dorsal vibratile fin of the rockling, which has been 

 believed to be a lure, is regarded by Dr. J. Stuart Thomson 

 as an organ for producing a current of water over numerous 

 termin.'il or taste buds situated in the skin of that region 

 of the body, which thus functions as a gusiatorv organ. 

 These taste organs are distinguished from the lateral line 

 organs by certain structural differences and by the fact 

 that they are innervated by the recurrent facial nerve, the 

 root of which is in the facial lobe of the medulla, which 

 lobe has been described by Herrick as part of the gustatory 



NO. 2192, VOL. 88] 



tract. Dr. Thomson's experiments indicate the existence of 

 a gustatory reaction in the rockling, some of the most 

 successful responses being obtained on placing Arenicola in 

 proximity to, but not in contact with, the taste buds of 

 the region under consideration. 



A Remarkable Egg of the Kestrel. 



Prof. Patten commented on an egg laid by a tame kestrel, 

 which has been in his possession eight years. The egg is 

 normal in size, but milky-white in colour and almost un- 

 spotted except at its larger end ; there are spots and 

 blotches of rich purple-brown intermixed with greyish- 

 purple, the whole pigmentation forming a broken zonular 

 band. Dr. Patten suggested that a highly nutritious hearty 

 meal, coming after a fast, and in a warm change of 

 weather, may have toned the bird to such a physiological 

 state that the ovaries became suflficiently active to induce 

 ovulation. 



Prof. R. J. Anderson brought forward a number of 

 details regarding the constitution of, and variation in, the 

 manus and pes of Primates, and contributed a note on the 

 manus of a young Indian elephant. 



J. H. Ash WORTH 



OLD AND NEW VIEWS ON THE TREATMENT 

 OF CONSUMPTION.'- 



T\R. THEODORE WILLIAMS stated that 255 years 

 had elapsed since William Harvey instituted this 

 festival, and that orations had been delivered in Latin 

 or English ever since in commemoration of benefactors, 

 and with Harvey's exhortation to the fellows and members 

 to study out the secrets of nature by way of experiment, 

 and to continue in mutual love and affection among them- 

 selves. He then proceeded to review the various steps of 

 Harvey's great discovery of the circulation of the blood, and 

 remarked that its author, in spite of the severest criticism, 

 lived to see it firmly established in the annals of medicine 

 and to witness the conversion of the greater number of his 

 opponents. The seed sown by this discovery, based on 

 observations and experiments, and put forth with con- 

 vincing logic by this most accurate observer, had revealed 

 to the world further scientific truths, which have been 

 elaborated by Harvey's successors in the arts of medicine 

 and of surgery, and have brought forth a harvest of 

 improvements — physiological, clinical, pathological, and 

 therapeutical — which added immensely to the total sum of 

 human health and happiness. Dr. Williams instanced as 

 examples the administration of anaesthetics, intravenous and 

 hypodermic injections, and treatment by vaccines, while 

 auscultation and the graphic methods of measuring blood 

 pressure and rhythm might also be counted as outcomes of 

 the knowledge initiated by Harvey's discovery. 



Harvey's views on tuberculosis are not known, though 

 his lost " medical observation " may have treated of these; 

 but the lecturer sketched the doctrines held by his con- 

 temporaries on this subject, and the treatment in vogue, 

 the former being somewhat obscure and the latter 

 mingling with hygienic and dietetic rules, which were to 

 some extent reasonable, prescriptions containing woodlice, 

 crabs' eyes, the simple powder of crabs' claws, red coral 

 and white amber in the form of powders or julep to 

 "temper the sharpness of the blood." The Royal touch 

 for the King's Evil continued to be believed in until a 

 much later date. Most of the theories of that time 

 assigned the cause of consumption to errors of digestion 

 or in the formation of lymph or chyle or blood, or to 

 defective respiration ; but they chiefly dwell on the in- 

 flammatory origin, and though long suspected, the vera 

 causa, viz. the tubercle bacillus, was never definitely proved 

 until Robert Koch appeared on the scene. Laennec and 

 other observers had meantime given scientific accounts of 

 the morbid anatomy of tubercle, and the treatment had 

 changed from an anti-inflammatory rdgime depending 

 largely on blood-letting to a tonic and building-up system, 



1 Abstract of the Harveian Oration delivered at the Royal College of 

 Physicians on October 18 by Dr. C. Theodore Williams. 



