72 MALL. [Vor. XIX. 
general way, for there is always more or less mingling of 
these two substances. 
TABEB I: 
NorMAL EMBRYOS OF THE FirST AND SECOND WEEKS. 
Specimen. Embryo. Ovum. : & 
o 
| = 
mm mm. days 
Retersiy of: svanas tenth ya .19 A (5) SS (0) 25 £8) 30 
Mertiens ace te Zee 21 
BreuSsiscfare space teats 5 38 
Reichert... nate essen: Sas 5B 42 
Siegenbeck van Heu- 
elo nasi, onto 325 CRG AAS 
Grail Speen. cee eistan 39 5.568 5 wks. 
Nopee arseisrstse sey ee 8 Tou y 7 41 
Keeipel sas a un ee eis Ty iSay O3s Gey) 2s © 
EU CeRMOd tae alee toe. it 8) 10.8 x 8.2 x6 34 
Grat SPs imac a: 1.54 DO Xi8.5.500.5 5 wks, 
INO ieee otoueia ve ahtastol TOK QOX5 40 
INOS23 Gras eeryee neice IoXIOXI0 41 
NO a2 5 Oricon ao life caters Zi, 10ox9x8 
INiOm 3 Sal ota mre. ters 2. Too 1s ro 49 
NOP ZO1s meme ns 2. 16X14 X12 42 
*References are given in my article in the Johns Hopkins Hospital 
Reports, Vol. IX, 1900. 
With this introduction to the primary changes in very 
young pathological ova we are ready to discuss those cases in 
which the amnion and embryo are destroyed, individually and 
in groups. In order to make this easier I have brought the 
specimens together in Table II, giving certain important data. 
Table I includes all of the normal ova I have been able to 
collect from the literature and is to be used for making com- 
parisons. By comparing the two tables it is noticed at once 
that the pathological ova are older and larger than the normal 
ones. But, judging by the changes within, it is highly prob- 
able that these began some time before the second week of 
pregnancy. If their ages are estimated by the size of the 
umbilical vesicles they would range themselves from one to 
