208 The Philippine Journal of Science 



There are also present in the coenobium four empty capsules 

 about 29 p wide that are either the remains of abortive oogonidia 

 or empty antheridia. 



Specimen 52.— This specimen is selected from among a be- 

 wildering variety on the same slide because it exhibits characters 

 of asexual and sexual coenobia in two daughters of the same 

 age. It is in glycerine, and the material with it shows very 

 little sign of shrinkage; the specimen in question, none at all. 

 The mother is 350 ^ wide and 320 ,* long. The protoplasts range 

 from about 4 p. at the back through 5 ^ in the middle to about 

 6 it at the front. The average spacing of the cells is about 7 ^ 

 and the number of cells is about 7,500. The two daughters are 

 150 by 200 and 160 by 200 p. The former contains two grand- 

 daughters, and the latter seventeen oogonidia and two androgo- 

 nidia. The granddaughters are 70 by 88 t* and 70 by 90 /*, and 

 each contains two gonidia of about 15 ,* in diameter. The sexual 

 daughter has the oogonidia about 12 to 15 p. wide, and the andro- 

 gonidia, located on opposite sides of the middle, are smaller. 

 One of these is undivided and about 8 ^ wide. The other has 

 formed a platelet of many sperms. This platelet is 7 p. thick 

 and about 20 n wide. 



It is thought that the descriptions given will suffice for a fair 

 picture of Merrillosphaera africana as it has been found at 

 Manila. Extended search would undoubtedly reveal variations 

 beyond the ranges of numbers and dimensions furnished by the 

 material described. As an example, an exceptional coenobium 

 was seen with three daughters and five bodies that had all the 

 appearance of oogonidia. Another example is a very small coe- 

 nobium, 126 by 152 p, that contains five sperm platelets and 

 seven oogonidia. 



SUMMARY 



The chief facts added to our knowledge of Merrillosphaera 

 africana by the account of the typical form of the species as 

 found at Manila are as follows : 



1. The somatic protoplasts are not connected by protoplasmic 

 filaments. 



2. The gonidia are differentiated at a very early stage in the 

 segmentation of the embryo. 



3. The gonidia reach a considerable size before dividing; 

 commonly about 55 /*, sometimes even 75 /a. 



4. The gonidia form pairs whose members are about equal in 

 size and are located symmetrically on opposite sides of the polar 



