1902] A MORPHOLOGICAL STUDY OF THUJA 251 



figures of Juniperus, and Chamberlain shows similar structures 

 associated with the male nuclei of Pinus Laricio. The finely 

 granular areas in the body cell of Pinus, as described by Miss 

 Ferguson (8), and the kinoplasmic regions described by Coker 

 (5) for the c^^ of Podocarpus seem to consist of the same sub- 

 stance. The spots, though generally present in the body cell, 

 were not found in the male cells of Thuja. These structures 

 are suggestive of the blepharoplasts of Ginkgo and certain cycads, 

 aad may be a survival of some such structures possessed by 

 ancestors from which the Pinaceae have descended. 



Before the appearance of the archegonium initials (June 16, 

 1901), the penetration of the pollen tube is relatively slow, but 

 at this time its downward movement is much accelerated. The 

 tube quickly pierces the remaining rows of nucellar cells, spreads 

 itself over the mouth of the archegonium complex, and absorbs 

 almost entirely the remnants of the neck cells, thus laying bare 

 the upper ends of the eggs {fig. 10)^ The body cell elongates 

 (fig. 5) and divides into two hemispherical cells of the same 

 size, this division taking place immediately before fertilization. 

 That both cells are functional is shown by the fact that when 

 only one pollen tube enters the complex two embryos are formed. 

 In many instances it was observed that the contents of the pollen 

 tube, which was in advance of the others, had fertilized two 

 eggs. The equal size of the male cells is another evidence that 

 both are functional. 



Arnoldi (i) finds in Cephalotaxus the two male cells of the 

 same size. Strasburger and also Belajeff (3) figure the male 

 cells of Juniperus as equal. Arnoldi's (2) figures of the male 

 cells of Sequoia show them to be equal. According to Coulter 

 (6) the male cells of Pmus Banksiana are alike in size and volume. 

 Chamberlain (4) finds the same to be true of Pifius Laricio. In 

 cycads male cells are equal. Belajeff (3) observed that inTaxus 

 one of the male cells is much smaller than the other and does 

 not enter the ^g^ at all, Coker (5) finds one functioning male 

 cell in Podocarpus. In Pinus Strobus Miss Ferguson (8) reports 

 them as unequal, with the larger cell invariably in advance. 



