Oct. 7, 1880] 



NATURE 



551 



others have recently called attention, and to which Mr. Riley 



I has contributed by his history of Epkauta and other Meloida. 

 I refer to the questions connected with so-called hypermetamor- 

 phosis in insects. In these cases there are changes of form 

 during the larval period greater than exist between larva and 

 pupa, or even between larva and imago, in some insects. There 

 are also slighter changes than these which very many larvte 

 undergo ; indeed it may safely be asserted that the newly- 

 hatched and the mature larvce of all external feeders differ from 

 each other in some important features. The differences are 

 really great (when compared to tho differences between genera 

 of the same family at a similar time of Ufe) in all lepidopterous 

 larvae, as well as in all Orthoptera which have come under my 

 notice. No attempt to co-ordinate these differences, or to study 



I their meanings, or to show the nature of their evident relationship 

 to hypermetamorphosis has ever been attempted. 



Not less inviting is the boundless region of investigation into 



I the habits of insects and their relation to their environment. 

 The impulse given to these studies by the rise of Darwinism, 

 and the sudden and curious importance they ha%'e assumed in 

 later investigations into the origin and kinship of insects, need 

 only to be mentioned to be acknowledged at once by all of you. 

 The variation in coloration and form exhibited by the same 

 insect at different seasons or in different stations, "sports," the 



: phenomena of dimorphism, and that world of differences be- 

 tween the sexes, bearing no direct relation to sexuality ; 

 mimicry also, phosphorescence and its relations to life, the 

 odours of insects, the relation of anthophilous insects to the 

 cjlours and fructification of flowers, the modes of communica- 

 tion between members of communities, the range and action of 

 the senses,' language, commensalism — these are simply a few 

 topics selected quite at random from hundreds which might be 

 suggested, in each of which new observations and comparative 

 studies are urgently demanded. 



The fundamental principles of the moi"phology of insects were 

 laid down by Savigny in some memorable memoirs more than 

 sixty years ago ; the contributions of no single author since that 

 time have added so much to our knowledge, notwithstanding 

 the aid that embryology has been able to bring. Nevertheless 

 there remain many unsolved problems in insect morphology 



' which by their nature are little likely to receive help from this 

 source. Let me mention three : — 



The first concerns the structure of the organs of flight. The 

 very nomenclature of the veins shows the disgraceful condition 

 of our philosophy of these parts ; the same terminology is not 

 employed in any two of the larger sub-orders of insects ; names 

 without number have been proposed, rarely however by any 

 author with a view to their applicability to any group outside 

 that which formed his special study ; and a tabular view which 

 should illustrate them all would be a curious sight. A careful study 

 of the main and subordinate veins, their relations to each other, 

 to the different regions of the wing, to the supporting parts of 

 the thorax and to the alar muscles, should be carried through the 

 entire order of insects ; by no means, either, neglecting their 

 development in time, and possibly deriving some assistance in 

 working out homologies by the study of their hypodermic 

 development. 



The second concerns the mouth parts. The general homo- 

 logies of these organs were clearly and accurately enough stated 

 by Savigny, though one may perhaps have a right to consider 

 the last word not yet said when one recalls Saussure's recent 

 claim to have found in Hemiinerus a second labium. What I 

 refer to, however, is another point : it relates to the appendages 

 of the maxilk'E and the labium. Considering the labium as a 

 soldered pair of secondary maxilla;, we have at the most, on 

 either pair of maxillK, three appendages upon either side. 

 These appendages, as you know, are very variously developed 

 in different sub-orders of insects, or even in the same sub-order ; 

 and it has at least not been shown, and I question if it can be 

 done, that the parts bearing similar names in different sub-orders 

 are always homologous organs. Here is a study as broad and 

 perhaps as difficult as the last. 



The third is the morphological significance of monstrosities, 

 especially of such as are termed monstrosities by excess. The 

 literature of the subject is very scattered, and the material much 

 more extensive than many of you may think. At present this 

 subject is, so to speak, only one of the curiosities of entomology, 

 but we may be confident that it will one day show important 

 relations to the story of life. 



' Notice Meyer's beautiful studies on thej'perception of sound by the 

 mosquito. 



After all the labours of Herold, Treviranus, Lyonet, Dufour 

 and dozens of other such industrious and illustrious workers, is 

 there anythmg important remaining to be done in the gross 

 anatomy of insects ? some of you would perhaps ask. Let the 

 recent work of some of our own number answer, which has 

 shown m the Hemiptera and Lepidoptera the existence of a curious 

 pumping arrangement by which nutritious fluids are forced into 

 the stomach. It is certainly strange that after all that has been 

 said as to the mode in which a butterfly feeds, no one should 

 have dissected a specimen with sufiicient care to have seen the 

 pharyngeal sac which Mr. Burgess will soon show us. No ! the 

 field is still an open one, as the annual reviews clearly show 

 The curious results of Flogel's studies of the brain, the oddlyl 

 constructed sense-organs found by Graber and Meyer (earlier 

 noticed briefly by Leydig) in the antenna; of Diptera, the im- 

 portant anatomical distinctions discovered by Forel in different 

 groups of ants, the strange modification of the tip of the spiral 

 tongue in Ophideres, which Darwin, Brietenbach, and Kiinckel 

 have discussed, and, above all, the extensive investigations of 

 the nervous system in insects generally which Brandt has recently 

 undertaken, the exquisite memoir of Grenacher on the structure 

 of the compound eye, and the keen researches of Graber in 

 various departments of insect anatomy, show by what has been 

 accomplished how many harvests are still unreaped. The micro- 

 tome, too, has put a new instrument of precision into the hands 

 of the investigator in the field. 



If these few words shall arouse in any one a higher ambition, 

 leading to better work, their aim will have been accomplished. 



SCIENTIFIC SERIALS 



American NaUiralisi, August 1880.— D. P. Penhallow, the 

 fabrication of Aino cloth.— H. D. Minot, English birds com- 

 pared with American. — ^J. S. Gardner, on the age of the 

 Laramie formation as indicated by its vegetable remains.— J. E. 

 Todd, on the flowering of Saxifraga sarmentosa. — Prof. A. N. 

 Prentiss, distribution of obnoxious insects by means of fungoid 

 growths. — Recent literature. — General notes. — Scientific news. 



September. — J. Walter Fewkes, the Siphonophores :— No. I, 

 the anatomy and development of Agalma. — Prof. A. N. Prentiss, 

 destruction of obnoxious insects by means of fungoid growths 

 (concluded) ; the result of these experiments would seem to 

 indicate plainly that yeast cannot be regarded as a reliable 

 remedy against such insects as commonly affect plants cultivated 

 in greenhouses or in windows, but the general question is by no 

 means as yet decided. — O. B. Johnson, birds of the Willamette 

 Valley, Oregon (concluded).— C. O. Whitman, Do flying-fish 

 fly? 



Annakn der Physik und Chemie, No. 8. — On electric ex- 

 pansion (continued), by G. Quincke. — Clausi' n' law and the 

 motion of the earth in space, by E. Budde. — On ihe dependence 

 of the electric conductivity of carbon on the temperature, by W. 

 Siemens. — On the phenomena in Geissler tubes under external 

 action, by E. Reitlinger and A. v. Urbanitzky — Complete 

 theory of tlie bifilar-magnetometer and new methods of deter- 

 mining the absolute horizontal intensity of the earth's magnetism, 

 as also the temperature and induction coefficients of magnets, by 

 H. Wild. — On the comparison of the electroHynamic funda- 

 mental law w ith experience, by R. Clausius. — On a direct trans- 

 formation of the vibrations of radiant heat into electricity, by W. 

 Hankel. — On fluorescence, by E. Lommel. — On the behaviour 

 of different heat rays in the reflection of polarised rays from 

 metals, by H. Knoblauch. — Remark on the heat conductivity of 

 mercury, by H. Herwig. — Remarks on H. Weber's mem lir on 

 heat-conductiou in liquids, by A. Winkelmann. — On air-resist- 

 ance, by G. Recknagel. — On the action of hollow, in comparison 

 with that of solid, steel magnets, by W. Holtz. 



No. 9. — On the compressibility of gases, by F. Roth. — On 

 the electric conductivity of some salt soluticjns, by J. H. Long. 

 — New experimental researches on fluorescence, l>y O. Lubarsch. 

 — On constants of refraction, by L. Lorenz. — Experimental re- 

 searches on refraction constants, by K. Prytz. — Theory of reflec- 

 tion and refraction at the limit of homogeneous, isotropic, 

 transparent bodies, with generalisation and extension of the 

 foundations of Neumann's method, by M. Rethy. — Thermal 

 theory of development of electricity, by J. 1,. HoorweiT. — On 

 the behaviour of electricity in gases, and especially in vacuum, 

 by F. Narr. — Defence of the law of corresponding b Mlmg tem- 

 peratures, by U. Diihring. — Equation of the state of atmospheric 



