PEROPHORA ANNECTENS. 85 



SYNOPSIS OF CONTENTS. 



Page. 



Introductory 37 



Historical accouut of owv knowledge of the genus Perophora 38 



Diagnosis of P. annectens 40 



1. General description of the species 41 



2. The test and the mesodermal origin of its cells 46 



3. The musculature 55 



4. The pharyngeal apparatus 56 



a. Parasites of the tentacles 57 



b. The branchial basket proper 59 



c. The endostyle 60 



d. The subneural gland and its duct 61 



5. The digestive tract 62 



Histologj' of the several parts 65 



The pyloric gland 68 



Parasites of the digestive ti'act 69 



(j. Reproductive system 71 



7. Circulatory system and blood 72 



Study of the movements of the heart, with a suggestion as to 



the cause of the reversal in the direction of its contractions . 73 



The blood corpuscles 76 



Bibliography 79 



Explanation of figures 81 



List of abbreviations 83 



