CONTENTS. ix 



Pages 

 hematochrome is not without analogy to the chlorophyl 



pigment. Opinion of naturalists upon the physiological 

 function of the so-called ocular spots. Observation of 

 M. Pouchet upon the eye of the Glenodinium po lyphemus. 

 This eye is composed of a pigmentary mass and of a 

 refringent body. Observations of M. Kiinstler upon the 

 eye of Phacus. Observation of Claparede and Lach- 

 mann. Observation of Lieberkiihn. Sensitiveness of the 

 Euglena to light. Experiments of Engelmann. The vesi- 

 cles of Miiller in the Loxodes rostrum 22-31 



n. 

 NUTRITION. 



Psychical phenomena connected with respiration. Search 

 for oxygen by the bacteria of putrefied matter. Observa- 

 tion of Engelmann 3J-34 



THE PSYCHOLOGY OF NUTRITION. 



Psychical phenomena connected with nutrition. Vegetable, 

 or holophytic, nutrition. The chromatophores. Structure 

 ot the chromatophores. Coincidence between the presence 

 of an eye and that of chlorophyl pigment. Comparison 

 between the Euglena and the Peranema. Nutrition by 

 endosmosis, or saprophytic. Animal nutrition, choice of 

 nutriment. Prehension of foods by the Amoeba, the Actin- 

 ophrys, the Monas, the Acineta. Opinion of M. Mau- 

 pas upon choice by preference. Capture of food. The 

 vorticelCiliates. The Hunter Ciliates. The Amphileptus. 

 The Didinium nasutum. Movements of defense and 

 flight 34-55 



IV. 

 COLONIES OF UNICELLULAR ORGANISMS. 



Colonies of unicellular organisms. Colonies of single-celled 

 organisms have their origin in the segmentations of a 

 mother-cellule. Temporary colonies which are formed 

 beneath the cuticle. The Gonium. The Eudoryna. The 



