: omcrioj. 
In cattle a f »ir ile born co-twin to n sale i sterlie in the 
rr-ajorlty of caeots und it? known 'iron,-, cattlo'os an a *froe-martin*• 
By ore authors all females of two-aoxed twins in cattle aro called 
frsa-mrtins* The proportion of the cases in t? ich uucb female io 
noraal is iven as follows; us&n (*44) one i • oi ? jht, L&er ( f 13) 
six in ninety-one, Lillie (*k 3) six io thirty-nine. These with one 
an thirty-six as fcr.;nd by the author* rake a total of 20 in CS7, or 
about 1 in 14. rtj-i roascn for the atari. ity is quite conclusively 
3uo»a by Liliio to be duo to definite and sufficient 
v .scular u:r» •• torbetween the circulations of the txi t in the 
placenta! eerbranee* in the absence of which tbs foraale io noraal. 
ihe -ale i • always normal. 
By toe claer autr.ors the froe-martin was classed a - 
b .rnauhroaite, or posude-her* aphrodite * as r-o ified r«J.e 
( .uTvan, '<.4)(J. Barry t art, ’10)(Bateson, # 13)* or as modified 
fecale (dunan, *4). Th ? last nursed author classed the* - m naies 
or ee females, according as the orpins are ore or lass ferule 
or «;ile in type. S'-degolborg (*6l) classed the ac transverse 
h sr aphrodites • 
atrxin (*4i) deacribthe case of a . uppoxed froe-r&rtin 
» ict hs obtained fre.m a i >ul©r when a year eld. » ich had an 
apparently feaalo sot of external ^onitaiia. revs, ventrally 
alo«u the body-wall, with ar acceu ory urethral openin dorsal 
to it. !1;e internal urogenital organs »sre decidedly ole, but 
o evide ce can be ^ot fro® his figure ae to the d.-velo wont of 
