394 



SCIEXCE. 



[Vol. VII, No. 169 



a 'most welcome addition,' to tbe stratigraphy of the 

 Taeonic range, of two plates of stratigraphical sec- 

 tions ' by Professor Hall, ' prepared by him forty to 

 forty- five years since.' 



Those two plates, or rather five plates, for that is 

 their exact number, were freely distributed by Pro- 

 fessor Hall as far back as Lyell's second visit to 

 America, 1845-46, and are well known on both sides 

 of the Atlantic. 



Professor Emmons refers to them in one of his 

 letters, dated Ealeigh, N.C., Dec. 28, 1860, of which 

 I published an extract in ' The Taeonic system and 

 its position in stratigraphic geology ' (Proc. Amer. 

 acad. arts and sciences, vol. xii. p. 128, Cambridge, 

 . as follows : " You are aware that [Professor] 

 Hall prepared five long sheets of sections illustrating 

 his views, and which extended from the Helderberg 

 to the Connecticut River, and from the Lake Cham- 

 plain to the Connecticut valley. . . . They were de- 

 signed to sustain his peculiar views. I have copies, 

 and I wish you had them. They are curiosities in 

 their way." 



It is evident that the views entertained bv Profes- 

 sor Hall, contesting the conclusions of Dr. Emmons, 

 have been placed before geologists in the United 

 States, Canada, and Europe since the appearance 

 of < The Taeonic system ' in 1842. 



Jules Marcou. 



Cambridge, Mass., April 23. 



A carnivorous butterfly larva. 



One of the most interesting of our butterflies is 

 that known as Fenesica tarquinius, — a unique ly- 

 cinid having the wings above brown-black in color, 

 with conspicuous orange markings both on primaries 

 and secondaries. It has a wide geographical range, 

 occurring very generally over North America, as 

 also in Asia. 



Donovan, in his ' Insects of India' (pi. xliv. fig. 1), 

 illustrates the butterfly rather poorly, but says noth- 

 ing about the larva ; Boisduval and LeConte (Hist, 

 des lep. et des chen. de VAmer. Sept., p. 128, pi. 37) 

 figure the larva, pupa, and imago under the name of 

 Polyommatus crataegi, and simply quote Abbot as 

 stating that the larva lives in several species of Cra- 

 taegus ; Scudder (Proc. Essex inst., iii. p. 163, 1862) 

 treats of it under the name of Polyommatus porsenna 

 (Syn. list of Amer. rurales, Bull. Buff. soc. nat. hist., 

 iii. p. 129, May, 1876), giving the food-plants of the 

 larva as Alnus, Ribesia, Vaccinium, and Viburnum 

 (later, in the American naturalist for August, 1869, 

 he gives the food-plants as follows, — 1 probably 

 arrow-wood, elder, and hawthorn'); Grote (Trans. 

 Amer. ent. soc, ii. p. 307) first proposed the generic 

 name of Fenesica, but says nothing about its larval 

 history; Strecker (Butt, and moths, etc. — Diurnes, 

 p. 103) repeats simply from Scudder ; while William 

 H. Edwards, in his admirable life-histories of butter- 

 flies, has not, so far, treated of this particular species. 

 In short, so far as the published records go, it has 

 been generally assumed that the larva feeds upon the 

 plants named. 



The object of this brief communication is to show 

 that in this larva we have one that is truly carnivo- 

 rous, — a fact which is extremely interesting, because, 

 so far as I can find, there is not another recorded 

 carnivorous butterfly larva ; and Mr. Scudder, who 

 has given great attention to the butterflies, writes me 

 in a recent letter, in reply to an inquiry on this point, 



that he cannot recall any mention of such. Quite a 

 number of heterocerous larvae are known to be car- 

 nivorous by exception, and not a few are so as a 

 rule. These are chiefly found among pyralids ; and 

 it is not necessary, for my present purpose, to refer 

 to the cases in detail. 



For some years, now, I have been studying the 

 remarkable life-habits of the Aphididae, and espe- 

 cially of some of the gall-making and leaf curling 

 species of Pemphiginae. 



In collecting material and making observations, I 

 have been assisted by Mr. Th. Pergande, who has, 

 on a number of occasions since 1880, found the larva 

 of this Fenesica associated with various plant-lice. 

 Among the species with which it has been thus found 

 associated are Pemphigus fraxinifolii Riley, which 

 curls the leaves of Fraxinus ; Schizoneura tessellata 

 Fitch, which crowds upon the branches of Alnus ; 

 and Pemphigus imbricator Fitch, which congregates 

 in large masses on Fagus. All these species produce 

 much flocculent and saccharine matter. 



The frequency with which this larva was found 

 among these plant- lice justified the suspicion that it 

 feeds upon them or derives benefit from them ; yet 

 up to 1885 the presumption was that it benefited 

 from the secretions of the plant-lice rather than from 

 the insects themselves. Last fall, however, Mr. Per- 

 gande obtained abundant evidence that the Fenesica 

 larva actually feeds upon the aphidids, and I thought 

 it worth while to call attention to this positive proof 

 of the carnivorous habits of the species. That the 

 different species of plant-lice are the normal food of 

 this larva, is rendered more than probable for the 

 following reasons : — 



1. Attempts to feed the larva upon the leaves upon 

 which it was found have proved futile, the larva 

 perishing rather than feed upon tbem. 



2. The food-plants given by the authorities are 

 such as are well known to harbor plant-lice. 



3. Mr. Scudder's authorities, as he informs me, 

 were picked up here and there ; and one of them for 

 alder, which he recalls, ' found it more commonly on 

 a limb among plant-lice.' 



4. Mr. Otto Lugger has frequently observed the 

 larva around Baltimore among Pemphigus imbricator 

 on beech, but never disassociated from the lice ; and 

 Judge Lawrence Johnson also found it in connection 

 with the same species around Shreveport, La., last 

 fall, and surmised that it might feed upon the Pemphi- 

 gus ; but neither of these observers were able to get 

 positive proof of the fact. C. V. Riley. 



Combined aerial and aquatic respiration. 



In investigating combiued aerial and aquatic respira- 

 tion in vertebrates, the following questions have pre- 

 sented themselves for solution, — questions which, 

 so far as we have been able to ascertain, have not 

 been previously answered by physiologists : — 



1. Is the aerial part of the respiration like that of 

 animals with an exclusively aerial respiration ? 



2. Is the aquatic part of the respiration like that 

 of animals with an exclusively aquatic respiration? 



In answer to these questions, we offer the follow- 

 ing facts and conclusion : — 



1. Observations upon the aquatic respiration of 

 soft-shelled turtles (Science, vi. p. 255 ; and Amer. 

 nat, 1886, p. 233) showed that the air taken from 

 the lungs of a turtle that had been immersed several 

 hours, had been almost completely deprived of its 



