After an interval which varies from ten to forty-five days, oviposition takes place. The female, resting on her back, bends the end of the abdomen forward over the hinder thoracic sterna, so that a chamber is formed into which the oviducts open. The eggs are passed into the chamber by one operation, usually during the night, and are plunged into a viscous greyish mucus with which it is filled. The spermatozoa pass out of the vermicular spermatophores, and mix with this fluid, in which the peculiarity of their form renders them readily recognisable. The spermatozoa are thus brought into close relation with the ova, but what actually becomes of them is unknown. The origin of the viscous matter which fills the abdominal chamber when the eggs are deposited in it, and the manner in which these become fixed to the abdominal limbs is discussed by Lereboullet (“Recherches sur le mode de fixation des œufs aux faux pattes abdominaux dans les Écrevisses.” Annales des Sciences Naturelles, 4e Ee. T. XIV. 1860), and by Braun (Arbeiten aus dem Zoologisch-Zootomischen Institut in Würzburg, II.). NOTE VI., CHAPTER I., p. 42. ATTACHMENT OF THE YOUNG CRAYFISH TO THE MOTHER. I observe that I had overlooked a passage in the Report on the award of the Prix Montyon for 1872, Comptes Rendus, LXXV. p. 1341, in which M. Chantran is stated to have ascertained that the young crayfishes fix themselves “en saisissant avec un de leurs pinces le filament qui suspend l’œuf à une fausse patte de la mère.” In the paper already cited from the Comptes Rendus for 1870, M. Chantran states that the young remain attached to the mother during ten days after hatching, that is to say, up to the first moult. Detached before this period, they die; but after the first moult, they sometimes leave the {352} mother and return to her again, up to twenty-eight days, when they become independent. In a note appended to M. Chantran’s paper, M. Robin states, that “the young are suspended to the abdomen of the mother by the intermediation of a chitinous hyaline filament, which extends from a point of the internal surface of the shell of the egg as far as the four most internal filaments of each of the lobes of the median membranous plate of the caudal appendage. The filaments exist when the embryos have not yet attained three-fourths of their development.” Is this a larval coat? Rathke does not mention it and I have seen nothing of it in those recently hatched young which I have had the opportunity of examining. NOTE VII., CHAPTER II., p. 64. THE “SALIVARY” GLANDS AND THE SO-CALLED “LIVER” OF THE CRAYFISH. Braun (Arbeiten aus dem Zoologisch-Zootomischen Institut in Würzburg, Bd. II. and III.) has described “salivary” glands in the walls of the œsophagus, in the metastoma, and in the first pair of maxillæ of the crayfish.