X, D, 2 



Wharton: Eggs of Ascaris lumbricoides 



113 



albuminous layer in the intestine by pressure or by the rubbing 

 of the eggs against one another. I have tried to remove this 

 layer from the eggs by various mechanical means, but have never 

 succeeded. Shaking or rubbing the eggs together or rolling them 

 about between tv^o surfaces may smooth down the mammilla- 

 tions, but it never removes the albuminous layer from around 

 the shell. The eggs may be broken, but the two layers of the 

 shell remain tightly attached, so I feel safe in saying that their 

 condition is not due to pressure. 



This form of egg is also often obtained when eggs are laid 

 in Kronecker's solution under certain conditions. Table I is a 

 record of the eggs laid by 56 individuals of Ascaris lumbricoides 

 kept in the solution in the laboratory. This table shows the 

 conditions under which the atypical eggs are laid. Of the 56 

 worms, 13 did not lay eggs. Two, Nos. 19 and 38, laid only 

 unfertilized eggs. All the others laid at least once, and the 

 majority laid several times. In all cases except Nos. 26, 27, 28, 

 and 29 from autopsy 3136 and No. 34 from autopsy 3137 the 

 first laying consisted of typical 2-layered mammillated eggs. 

 In the succeeding layings the outer albuminous layer became 

 much thinner and less typical, and in the majority of cases where 

 laying continued for several days it disappeared entirely, and 

 only eggs with a smooth surface, without the albuminous layer 



Table I. — Eggs laid by Ascaris lumbricoides in Kronecker's solution. 



No. 

 in se- 

 ries. 



Au- 

 topsy 

 No. of 

 host. 



Date 

 obtained. 



Day. 



1. 



2. 



3. 



4. 



5. 



6. 



7. 



8. 



9. 



10. 



11. 



12. 



1 



2 



3 



4 



6 



6 



7 



8 



9 



10 



11 



12 



»13 



«14 



«15 



16 



17 



18 



bl9 



3104 

 3104 

 3104 

 3104 

 3104 

 3110 

 3113 

 3113 

 3113 

 3113 

 3113 

 3113 

 3114 

 3114 

 3114 

 3118 

 3118 

 3118 

 3125 



Apr. 4 

 —.do.... 

 ....do...- 

 .-..do.... 

 ....do .... 



Apr. 7 

 ....do.— 

 ...-do— . 

 ....do.... 

 ....do...- 

 ...-do -... 

 — .do—. 



Apr. 8 

 -..do — . 

 ..-.do..- 



Apr. 13 

 ....do .... 

 ....do..- 



Apr. 14 



X 

 X 

 X 

 X 

 X 



o 



X 

 X 

 X 

 X 



o 



X 

 

 

 

 

 



o 

 o 



X 

 



o 

 o 

 o 

 o 



X 



o 



X 

 X 

 X 



o 



X 

 X 



o 

 o 





 

 



X 

 



o 

 o 



X— 



o 



X 

 X 

 X 

 X 



o 



X 

 X 

 X 

 X 

 

 D 



o 











UY 

 



X— 



o 







X 



o 

 o 



K 



X 



X 



o 

 o 





 D 



UY 

 

 D 

 D 

 D 



o 





 



UY 

 



U— 

 



X— 



o 

 o 

 o 



D 

 D 

 D 























































X 

 



X 



D 

 D 

 D 











































o 







X— 



X 



X- 



X— 

 D 

 O 

 

 



D 























D 



o 

















D 

 D 











































o 

 o 



o 







O 

 



D 

 













U- 



o 



D 







