1887.] 27 



cannot but think that there is here a transitory state, or even a still lower degTee of 

 development, which may be definite in some species of the same family or any other 

 group. We may even conceive that the males may be rudimentary in such a 

 manner that they may be reduced, in the body of the mother, to sexual elements, 

 and thus there may be produced there a kind of false hermaphroditism ; they might 

 even be represented in the lowest degree by undifferentiated elements, but which, 

 nevertheless, come into connection with the ovules ; it may thus happen that the 

 so-called pseuduva may be identical, in their evolution, with ordinary eggs, and, as in 

 the known hypothesis in connection with agamic Aphides, that the development of 

 the ovules was determined by the hermaphroditism of the females. Be this as it 

 may, as the males es(!ape observation in every case, one cannot fail to infer that par- 

 thenogenesis or pedogenesis, which is a form of it, exists. In fine, we conceive that 

 these reduced males may be able, in certain seasons and under certain influences, in 

 consequence of a more retarded evolution of the genital products, to acquire a 

 perfect development and exhibit normal characteristics. 



" It appears possible to apply these considerations, until there is proof to the 

 contrary, to the various parthenogenetic animals, with the exception, perhaps, of 

 certain Hymenoptera among which the phenomena are more complicated. Partheno- 

 genesis constitutes a peculiar fact which hitherto has not received sufficient explana- 

 tion, and it may be, that like many other facts apparently aberrant, it will one day 

 come under the general law of sexual reproduction." 



The discovery of the male of Leeanium hesperidum, although the 

 mode of action or influence of this sex has yet to be elucidated, is of 

 itself of very great interest, and in the inferences and suggestions 

 arising from it, with respect to the recondite subject of parthenogenesis 

 in general, has a significance and importance not exceeded by any 

 revelation oE modern science. 



Lecanium depuessum. 



Leeanium depressum, Sign., Ess. Cochin., p. 269, pi. 12, llg. 11, 11 », and 116. 



$ . Scale convex more or less according to age. Form broad-oval or ovate, some- 

 times one side nearly straight, or incurved so much that the outline is subreniforni 

 or subpyriform. Colour pale greenish-yellow ; a black or dark median line, not 

 carinate ; the disc with black dotted lines disposed so as to form marquetry, in the 

 mature form these coalesce and make patches, but leaving the ground colour clear in 

 places, usually two anterior and two posterior ; lower down straight dotted lines 

 radiate to the margin all round ; on the anterior half on each side two distinct dark- 

 dotted carinse with pale ends extend to the margin, the posterior ones nearly at a 

 right angle, the anterior oblique, all of them corresponding to the legs beneath. 

 Under a high power the surface is seen to be covered with a reticulation of irregular, 

 shallow cells, and the black dots are resolved into spots with a pale centre or 

 ocellus, each spot, situate in a mesh, appears as an inlaid plate of tesselation. Anal 

 point yellow. Under-side all pale, except the abdomen, which is black. Antennae 

 of eight joints, the 3rd longest. Length, 4, breadth, 3-5 mm. 



This, description differs from that of Signoret in that he gives the 

 colour of the scale as brown, which docs not occur, in my experience. 



C 2 



