Millet, Descartes, sa vie, ses travaux, ses decouvertes avant 1637 (Paris, 1867), and Hist.
The simple form of ocellus described in the foregoing paragraph may become folded into a pit or cup, the interior of which becomes filled with a clear gelatinous secretion forming a sort of vitreous Modified after Linko, Travaux Soc. Imp. Nat., St.
Maspero, Rec. de travaux (1905), xxvii.
For more detailed bibliographical information see Apercu des travaux zoo-ge'ographiques, published at St Petersburg in connexion with the Exhibition of 1878; and the index Ukazatel Russkoi Literatury for natural science, mathematics and medicine, published since 1872 by the Society of the Kiev University.
It is instructive to observe in Egypt the form which old traditions have taken in Manetho (Maspero, Rec. de travaux, xxvii., 1905, 1.22 seq.); cf.