158 



TEXT-BOOK OF EMBRYOLOGY. 



can be expressed fairly accurately by the square root of the length multiplied by 

 ioo (•» /length in mm. x ioo). In embryos between ioo and 220 mm. the age 

 in days is about the same as the length in millimeters. 



Some of the most important embryos which have been described are 

 listed in the accompanying table, no pretense being made of giving a complete 

 list. The table is compiled largely from the more extensive tables of Mall 

 and merely serves to indicate some of the younger embryos with fairly well- 

 known histories, from which certain conclusions have been drawn concerning 

 the relation of age to length. The periodicals in which descriptions may be 

 found are given with the authors' names in "References for Further Study" 

 at the end of this chapter. 



No. 



9 

 10 

 11 

 12 



J 3 

 14 

 J 5 

 16 



*7 

 18 



J 9 

 20 

 21 

 22 



2 3 

 24 

 2 5 

 26 



Observer 



Dimensions of chori- 

 onic vesicle in 

 millimeters 



Bryce-Teacher 1.9 x 1.1 x .95 



Leopold 1.4 x .9 x .8 



Peters 3. x 1.5 x 1.5 



Reichert 5-5*3. 3 



von Spee 7-5x5-5 



Mall 10.5 x 7. x 7 



Eternod 10.8 x 8.2 x 6 .... 



von Spee 10 x 8.5 x 6.5 ... . 



Mall 18. x 18 x 8 



Thomson. ... 5.7 



His | 15x12.5 



Thomson 15 x 10 



von Spee I 15x14 



Janosik i 8 



His I 14 x 11 i 48 



Mall 24 x 16 x 9 I 42 



Number 

 of days be- 

 tween last 

 menstrual 

 period and 



abortion 



3°- 

 42. 



35- 

 41. 



34-- 



35- ■ 



41. . 



42. . 

 40. . 

 14. . 

 42. . 

 43 •■ 



Number of days 

 between first 

 lapsed period 

 and abortion 



14- 



I 3- 



I 3- 

 14- 

 12. 



His J 30 x 25. 



His j 25 x 20. 



Meyer , 22 



Stubenrauch . 



Mall 



His 



Meyer 



Ecker 



His 30 x 27 



His.. . 35x28. 



25 x 25 . 

 21 x 17. 

 45 



5 J - 



18.. 

 45-- 

 52-- 

 57- ■ 

 28.. 

 60.. 

 61.. 

 61.. 



14- 

 15 

 20. 



17.... 

 24 



2 9 (?). 



3 2 - 

 33- 

 35- 



Probable 

 age in days 



13-M- ■ 



14. 



1 3- 



12. 



13- 

 14. 



14.. 

 14. . 



I 5- ■ 

 20. . 

 14 . 



2 3- ■ 

 21. . 

 18.. 



17- ■ 



24. 



27.. 



28. 



3 2 - 



33- 



35 



Length of 

 embryo in 

 millimeters 



0.15 

 0.19., 



°-37- 

 0.8. . 

 1.3.. 



1-54 

 2.1. . 

 2.1. . 

 2.15. 



2.5- ■ 

 2.69.. 

 3.... 

 3.2... 

 4.. . 



4 



5.... 

 5.2.. 

 6.... 

 7. . . . 



7-75- 

 8... 

 10. . 

 11. . 

 13.6. 



Normal, Abnormal and Pathological Embryos. 



In the majority of cases of spontaneous abortion it is not possible to examine 

 the uterus; but in those cases where it is possible, examination frequently shows 

 abnormal or pathological conditions. As might be expected, the embryos 

 obtained from abnormal or pathological uteri very frequently show anom- 

 alous conditions or pathological changes, or both. Since many of the 



