SUPPOSED NEW SPECIES OF LEUCANIA. 185 



streak above the median vein of the primaries and the better-defined 

 black or dark markings" {'frans. Ent. Soc. Lonr/., 1890, pp. 660-661). 

 There is no need to recapitulate our criticism of this statement after a 

 close inspection of the series in the British Museum collection, except 

 to say that there we found seven specimens of European L. ^tra)iii)i)'a 

 mixed up with a row of American L. jiallcns. 



Speaking from memory, we have an idea that the American L. 

 pallvns had more or less strongly developed traces of the dotted 

 elbowed line, and, in this respect, resembled the newly-described form 

 favicoJor. 



SCIENTIFIC NOTES AND OBSERVATIONS. 



Insect vision. — The latest that has been discovered relating to this 

 subject will always be of interest. Hence the following: — " It has 

 always been assumed that Howers attracted insects, in large measure, 

 at least, by the splendour of their inflorescence. Some recent 

 experiments by Plateau, recorded in the Bulletin <if the Behjian 

 Acculemij, throw doubt upon this assumption. In a considerable bed 

 of showy dahlias, Plateau concealed from sight the highly-coloured 

 rays of some of the flowers, exposing only the disc, and in a second 

 series of experiments the disc also, but independently, either by means 

 of coloured papers or by green leaves secured in place by pins. 

 Butterflies and bees sought these flowers with the same avidity, and 

 apparently the same frequency as the fully exposed flowers in the 

 same patch, the bees particularly pushing their way beneath the 

 obstacles to reach them, though not always with success. Plateau con- 

 cludes that they are guided far more by their perception of odours 

 than by vision of bright and contrasted colours. In a second com- 

 munication to the same Academy, Plateau gives the details of another 

 set of experiments to determine whether a wide-meshed net presents 

 any obstacle to the passage of a flying insect, which, as far as room 

 was concerned, could easily pass in flight through the interstices. He 

 finds that while such nets do not absolutely prevent passage on the 

 wing, insects almost invariably act before one they wish to pass as if 

 they could not distinguish the aperture, ending by alighting on the 

 mesh and crawling through. He reasons that, through the lack of 

 distinct and sharp vision, the threads of the net produce the illusion of 

 a continuous surface, as for us the hatchures of an engraving seen 

 at a distance" (Psi/che). — J. W. Tutt. 



Egg parasites.— I have recently been engaged in reading up the 

 back volumes of The Kntumoloi/isf.s liecord, and was particularly in- 

 terested in your treatise on the " Ovum or Egg " (May and June, 

 1894), and I am thus induced to send you the following account, 

 which may possibly be of interest in connection Avith this subject. 

 During October, 1894, I took a batch of ova of Orijijia antiqua. The 

 remains of a $ with the eggs, I discovered on the empty cocoon, on the 

 underside of a bramble leaf. There was nothing unusual in this, but 

 I was greatly surprised in the following spring to observe that the 

 greater number of eggs hatched out a small species of ichneumon, the 

 remainder having previously produced the ordinary larvfe. I had kept 

 an eye on the ova, as I noted they had not all hatched. This may be 

 known to science, but in your article I do not see that ichneumons are 



