MERRILLOSPHAERA, A NEW GENUS OF THE 
VOLVOCACEAE 
By WALTER R. SHAW 
Of the Department of Botany, College of Liberal Arts, University of the 
Philippines, Manila 
EIGHT PLATES AND ONE TEXT FIGURE 
CONTENTS 
INTRODUCTION. MERRILLOSPHAERA CARTERI VAR, TYPICA 
MERRILLOSPHAERA CARTERI (STEIN) VAR. NOV. 
COMB. NOV. VAR, MANILANA VAR. MERRILLOSPHAERA CARTERI VAR. WEIS- 
NOV. MANNIA (POWERS) COMB. NOV. 
Description of type specimen. MERRILLOSPHAERA MIGULAE SP. NOV. 
Asexual cotype specimens. MERRILLOSPHAERA TERTIA (MEYER) 
Female coenobia. COMB. NOV. 
Male coenobia. MERRILLOSPHAERA AFRICANA (WEST) 
Forms of asexual coenobia. COMB. NOV, 
A smaller form of the species. DIAGNOSES OF GENUS, SPECIES, AND 
Cell membranes. VARIETIES, 
Mixed reproductive bodies. 
INTRODUCTION 
In 1859, Carter described what he supposed to be Volvox 
globator Ehrenberg, which he found in India, presumably in 
the neighborhood of Bombay. From Carter’s description, Stein 
(78, p. 184) recognized the plant as specifically distinct from 
all that had been described, and he named it Volvox carteri. 
Stein improperly regarded it as intermediate between the spe- 
cies V. globator and V. aureus of Ehrenberg, whereas in reality 
it is neither intermediate between those species nor even so 
closely related to either of them as they are to each other. 
One of the several members of the subfamily Volvoceae which 
I have collected at Manila so nearly fits Carter’s description 
that I shall treat it here as a mere variety. Yet this species 
differs so much from the earlier described species of Volvox 
that I shall assign it, with others, to a new genus. Carter noted 
the absence of protoplasmic connecting filaments between the 
somatic or vegetative protoplasts. There had long been in my 
mind a question as to the propriety of including in the genus 
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