218 bulletin: museum of comparative zoology. 



leading to the formation of the first maturation spindle begin before the 

 egg is set free from that organ. The least developed of the eggs found 

 in the oviduct showed the first maturation spindle already established, 

 and nearly the whole of the germinative vesicle involved in the spindle. 



2. LiMAX Eggs in the Albumen Gland. 



I found a few eggs in the albumen gland imbedded in a small mass of 

 albumen ; there was no trace of an egg membrane. In these eggs the 

 first maturation spindle was in every case completely formed and lying 

 near the middle of the egg. There was no indication of the presence of 

 a spermatozoon in the eggs found either in the oviduct or in the albumen 

 gland. 



3. LiMAX Eggs in the Uterus. 



In the uterus of liimax agrestis I found a few eggs in which the first 

 maturation spindle had not yet begun to move toward the periphery. 

 The earliest stage of the eggs of Limax maximus secured was found in 

 the uterus, no eggs of this species having been obtained either in the 

 oviduct or in the albumen gland. In these (L. maximus) eggs the first 

 maturation spindle was eccentric in position, the centre of one centro- 

 sphere being near the periphery of the egg. Uterine eggs were kept 

 separate from eggs already laid, and likewise from eggs obtained from 

 the oviduct or the albumen gland, but no note was taken of the exact 

 location of eggs in the uterus, whether they were nearer the albumen 

 gland or the external opening of the uterus. 



The eggs of Limax maximus found in the uterus ranged from a stage 

 in which one centrosphere of the first maturation spindle was nearly 

 peripheral in position to a stage in which the first polar cell was com- 

 pletely formed. Since these eggs were found in the uterus of an animal 

 killed while engaged in laying, one is safe in assuming that the earliest 

 stage likely to be found in an egg of Limax maximus already laid is one 

 in which the first polar cell has been formed. Unfortunately, not a 

 sufficient number of eggs of Limax agrestis were preserved to furnish any 

 definite notion of the earliest and latest stages to be found in the uterus 

 of this species. In the few eggs from the uterus that were sectioned and 

 examined, the first maturation spindle was nearly central. 



The earliest indication of a spermatozoon within the egg was noted in 

 uterine eggs. The fact that in some cases (L. agrestis) the head of the 

 spermatozoon was still attached to the filament indicates that penetra- 

 tion had taken place only a very short time before fixation by the killing 



