562 EMBRYOLOGY OF THE LOWER VERTEBRATES < 11. 



Berlin Aquarium it has been observed that pairs of eggs were deposited 

 at intervals of about ten days. The methods of technique mentioned 

 in connexion with the Skate are also applicable to the eggs of 

 Scyllium. 



It should not be forgotten that, as mentioned earlier in this 



ot ucV 



Ki';. 248. Raia batis, embryos. 



nt, at rial portion of In-art ; E, eye ; c, conus ; f.g, foregut ; //, heart ; /, lens ; /i, liver ; ot, ot<-oyst ; 

 l-lu. piiH-al or^an ; il>, thin roof of fourth venti iolr ; P.O. I, i-tc., visi-eral clefts ; I/.N. yolk-stalk ; \ , Nil, 

 VIII. cianial !, 



volume, one of the greatest desiderata in Vertebrate rinl.ryolo-y. is 

 ;in oviparous shark with rggs of small si/c. 



TKLEOSTOMI. The most archaic ;m<l tlierclnn' tin- murjilmli^ii-ally 

 most iiiijM*rtai;t, sur\ivin;_f nicinhcr nl' this ^roup is .J'v/yjitf ri'x and 

 StrenuOOJ ellnrl-s haN-- hccn made 1 ohlain l (lt'vcl()})iiiental matrrial. 

 Harrington lost liis life on an expedition to the Nilr \\ith this ul.j.M-.i. 

 Budgett made l,wo cx]cditioiiH to UK- (Jumbia, one to Nigeria and 



