Charles J. Chamberlain 



(saturated aqueous solution). From the gentian violet the preparations were trans- 

 ferred directly to absolute alcohol, where they were quickly dehydrated, the process 

 being hastened by moving the slide to and fro in the alcohol. Clove oil was used for 

 clearing. The clove oil should be rinsed ofip with good cedar oil, otherwise the gentian 

 violet gradually fades. When orange G was used the preparations were taken from 

 the gentian violet, dipped a few times in water, stained for one minute in orange, and 

 then transferred to the absolute alcohol. 



In studying the preparations hollow glass globes, filled with various solutions, 

 served as ray filters and condensers. A light blue solution of ammonia copper sul- 

 phate was used for most of the work, but occasionally a light violet solution of per- 

 manganate of potash, imitating the gentian violet stain, gave a sharper differentiation of 

 the kinoplasmic structures. 



While the work deals chiefly with the first three divisions of the germinating 

 spore of Pellia epiphylla, and in these divisions is largely confined to the centro- 

 spheres, asters, and spindle, mitosis was studied in other phases of the life-history of 

 this genus, and also in several other liverworts, among which were Coriocephalus, 

 Marchantia, Aneura, Pallavicinia, Scapania^ Lophocolea, and Porella. 



The principal results of the investigation were presented in a Vortrag before Pro- 

 fessor Strasburger and the advanced students of the Bonn laboratory in February, 

 1902, and in July of the same year a brief r6sum6 was presented before the botanical 

 section of the American Association for the Advancement of Science. 



THE SPORE MOTHER-CELL 



The spore mother-cell was observed in Pellia epiphylla, P. calycina, Aneura 

 multifida, and in Porella platyphylla. In all of these forms the nucleus occupies a 

 central position during the development of the lobes which are to become spores. It 

 seems probable that the nucleus is concerned in the formation of the lobes. We found 

 nothing to support Davis's (7) statement that the nucleus lies in one of the lobes until 

 shortly before the first division of the mother-cell. No quadripolar spindles, like that 

 described by Farmer (7) for Pallavicinia, were found in any of the above-mentioned 

 forms. On the contrary, the four spores in all these cases are formed by two succes- 

 sive divisions, as described by Farmer (10) and by Davis (7) for Pellia epiphylla. 

 Unfortunately, no material of Pallavicinia in this stage was available, but the striking 

 resemblance of Farmer's (8) figures to the mitoses in deeply lobed mother-cells of other 

 Jungermanniales leads us to suggest, as Davis (7) has already done, that Farmer (8) 

 may have misinterpreted the quadripolar figure in this genus. 



. THE GERMINATING SPORE 



The first, second, and third mitoses in the germinating spore of Pellia cannot be 

 regarded as distinct types, for with diligent searching one could select a series of 

 mitoses at the'second division, or even at the third, which would be identical with a 



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