NOTES. 351 
-the extremities of the posterior pair are inclosed in the groove of the 
anterior pair; and the end of the vas deferens becoming: everted and 
prominent, the seminal matter is poured out, and runs slowly along the 
groove of the anterior appendage to its destination, where it hardens and 
assumes a vermicular aspect. The filaments of which it is composed are, 
in fact, tubular spermatophores, and consist of a tough case or sheath 
filled with seminal matter. The spoon-shaped extremity of the second 
abdominal appendage, working backwards and forwards in the groove 
of the anterior appendage, clears the seminal matter out of it, and 
prevents it from becoming choked. 
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 vermicnlar 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 ceufs aux faux pattes abdominaux dans les 
Ferevisses,” Annales des Sciences Naturelles, 4e Ee. T. XIV. 1860), 
and by Braun (Arbeiten aus dem Zoologisch-Zootomischen Institut in 
Wiirzburg, IT.). 
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, LXXY, 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 1’ceuf 4 une fausse patte de la mére.” 
In the paper already cited from the Comptes Rendus for 1870, M. Chan- 
tran 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 
