22,2 Shaw: Merrillosphaera africana 187 



cation, of about 455 by 525 p, 420 by 490 p, and 475 by 595 * 

 The somatic cells show most clearly about the anterior poles 

 where they are most widely spaced. In West's figure 10 (Plate 

 7, fig. 48) the somatic protoplasts are about 5 or 6 ^ in diameter, 

 and near the anterior pole they are spaced about 25 ft between 

 centers. On the sides of the coenobium the spacing is about 

 19 to 21 fx. The number of somatic cells I estimate to be be- 

 tween 2,000 and 2,500. West described the cells as having no 

 observable protoplasmic connections. 3 



The daughters, as shown by his micrographs, are three, four, 

 and three, respectively, and the granddaughters two, two, and 

 three in his figure 8 (Plate 7, fig. 49) ; four in one and probably 

 all of the daughters in his figure 9 (Plate 7, fig. 50) ; and 

 three, four, and four in his figure 10 (Plate 7, fig. 48). The 

 latter figure shows within the granddaughters the fourth gener- 

 ation, but not sufficiently clearly for counting the great grand- 

 daughters or for determining whether they are gomdia or 

 embryos. 



The daughter coenobia, except when an odd one is present, 

 occur in pairs and are compressed between their sisters and 

 the wall of the mother coenobium. The mothers in West's 

 figures 8 and 10 (Plate 7, figs. 49 and 48) have each one pair 

 of larger and more-elongated daughters a little in advance of 

 the middle of the mother, and an unpaired smaller daughter 

 in the back part of the mother. Each of the larger, paired 

 daughters is longer than half the length of the mother and 

 narrower than half the width of the mother. As the trans- 

 verse diameters which they show in the picture plane are short- 

 ened by compression against their sisters, their transverse 

 diameters normal to the picture plane are probably considerably 

 greater. The mother shown by West's figure 9 (Plate 7, fig. 

 50) has two pairs of daughters that lie in median planes normal 

 to one another, the members of the pair near the middle being 

 somewhat larger than those of the pair in the back, but all 

 having dimensions considerably less than half as great as the 

 corresponding measurements of the mother coenobium. 



The granddaughters show the pairing also. One larger 

 daughter in West's figure 8 (Plate 7, fig. 49) contains only a pair 

 of globose granddaughters about 50 and 57 M in diameter, 

 this being about a quarter of the width of the daughter. They 



•His mention in a later paper (West, '18, p. 426) of delicate connecting 

 strands of protoplasm seems to have been a slip. 



