506 Philippine Journal of Science iai» 



tions. In many of the sexual daughters sperm platelets are 

 present in the unborn daughters. In no case were antheridial 

 coenobia seen in the mother coenobia of this species, though 

 they are common in the T 7 . africanus coenobia mixed with them. 

 The staining of this material does not fit it for making photo- 

 micrographs with distinct detail. For this reason I present 

 without illustration the descriptive data pertaining to two 

 selected specimens : 



Specimen 25. — Mother eoenobium, 250 by 275 m. Estimate of somatic 

 cells, 2,850. Daughters, 7; three asexual in a forward group and four 

 sexual in two pairs in the posterior half of the mother. Each asexual 

 daughter contains eight gonidia, of which the diameters range from 18 to 

 21 m, 18 to 21 m, and 19 to 25 m. The youngest asexual daughter measures 

 70 by 75 n, and the eldest, 90 by 95 m. The' latter has an average somatic 

 cell width of 3.7 /«■ and an estimated number of somatic cells of 2,190. 

 One of the sexual daughters measures 95 by 110 M and has an average 

 somatic cell width of 7.5 m and an estimated number of somatic cells of 645. 

 It contains eight oogonia of about 19 ^ and eight antheridia. The latter are 

 sperm platelets more or less dished. Another sexual daughter contains 

 twelve oogonia and four antheridia, one of the latter being hemispherieally 

 cup-shaped. A measurement of 23 m across the mouth of the cup, with about 

 1.8 m for the spacing of the sperms, gives an estimate of more than two 

 hundred fifty-six for the number of sperms in this antheridium. The next 

 daughter contains sixteen oogonia and no antheridia, and the last one 

 fifteen oogonia and one antheridium. 



A number of gonidia, or gonidial products, greater than eight 

 was noticed in only one specimen that could be certainly iden- 

 tified as belonging to this species. 2 It is on the same slide as 

 the preceding. The generic characters presented by the em- 

 bryos render its identity unmistakable. A description of it 

 follows : 



Specimen 26.— Coenobium, 210 by 220 m. Somatic cell width, 8 /*. Num- 

 ber of cells, 2,570. Contents, 4 gonidia and 5 embryos. The gonidia lie 

 near the coenobial equator, in advance of it, and measure 44, 50, 50, and 

 54 * The embryos are grouped in the hinder part of the mother. Four 

 are in the closing bowl stage and one, the hindmost, is in the bullet stage. 



The extent of the cell membranes around the gonidia and the 

 embryos produced from them is not easily discernible, even in 

 much of the material which has been stained with Bismarck 

 brown. Although the inner limit usually becomes visible as 



■ The only other specimen containing more than eight gonidia on this 

 slide is one with dimensions 190 by 205 m; average cell width, 4.2 ft; 

 number of cells, 7,800; and nine gonidia, all of which measure about 

 40 v., except one near the posterior pole, which is 36 p.. This is probably 

 a specimen of Volvox carteri Stein (V. wcismannia Powers). 



