DEVELOPMENT OF L1SSENCEPHALA. 723 



larger than those glands, the superiority of size depending on 

 their large epididymis, with the adherent remains of the TTolffian 

 body. They continue within the abdomen for six weeks after 

 uterine birth.' 1 The nervous system alone is embryonic, fig. 585. 

 401. Development of Lissencephala. - -In Lyencephala, of which 

 the uteri undergo least change of dimensions .during the charac- 



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teristic brief gestation, those tubes have the definitely organised 



o o 



and persistent lining membrane described, pp. 679, 685. 



In the placental Mammals of which the uteri undergo wholly 

 or locally great and rapid changes of size and capacity the lining 

 of the incubatory part is less differentiated. In some it is but 

 remotely allied to the class of membranes called ' mucous ' : canals 

 so lined are habitually traversed by the matters they have to 

 convey. The transmitting function of the womb is seldom exer- 

 cised in the course of life, with long intervals of rest : its lining- 

 has a higher, organising, office : it differs from mucous mem- 



O O O ' 



brane in the absence of ( submucous areolar tissue ' (p. 439, 

 fig. 361, c, d), or any such medium of connection with, or recep- 

 tion of, vessels from the 

 muscular coat : it is a 

 pulpy substance, in which 

 corpuscles or nuclei a- 

 bundantly, and fibre-cells 

 more sparingly, formify : 

 it receives directly from 

 the fleshy substance of the 

 womb its vascular sup- 

 ply ; and IS perforated by section of lining substance, human uterus ; iiat. size. 



the minute canals, spar- CCXLVI". 



ingly exuding fluid, termed f uterine or utricular glands.' A cili- 

 ate epithelium may be distinguished on the free surface in most 

 Mammals ; non-ciliate cell-deposit occupies more or less of the 

 * utriculi.' These, in fig. 570, are indicated by the pale tortuous 



i LXXV'. p. 337 (1834). Such is the difficulty of giving up a strange or ' telling' state- 

 ment, which has once gained currency, that we read: ' Les petits ne se developpent 

 pas conime d' ordinaire dans la poche uterine, rnais sont promptement expulses au 

 dehors, et naisseut dans un etat d' imperfection telle qu'on ue peut les comparer qu'a 

 des embryons a peine ebauches. Ce sont des petits corps gelatiueux, informes et 

 incapables de mouvement, dont les divers organes ne sont pas encore distincts, etdont 

 1'existence serait impossible si la nature n'avait assure leur conservation par des 

 moyens particuliers.' CCLXV". Even M. Pouchet, iisually so conscientiously accurate, 

 writes : 'Le produit de la generation qui, en arrivant la (the pouch), n'est qu'un simple 

 ovule encore baigne de fiuides albumineux, se trouve pose sur les tetines.' (ccxci". 

 p. 262, 18-il). My observations on the Kangaroo were confirmed by those of Meigs 

 on the Opossum (CCLXXVIII". 1847X 



u A -2 



