INDEX AND GLOSSARY. 427 



Phanerogamia, 155 (Gr. phaneros, visible, and gamos, mar- 

 riage). 



Physograda, 167. An order of Acalephs, now referred to 

 Hydroida. 



Physalia, 167. Portuguese man-of-war. A genus of Hy- 

 droida. Sub-class, Siphonaphora. 



Pleurosigma, 56. 



Polariscope, 42, 99. 



Polycysti.na, 95, 160. An order of Rhizopods. 



Polymorphism, 136, 324. Various forms produced by the 

 same germ. 



Polyps, 164 (Gr. polus, many ; pous, foot). 



Polyzoa, 168 (Gr. polus, many ; zoa, animals). 



Polypary, 166. The arborescent structure or Hydroids. 



Polypite, 166. The nutritive zooid or compound. 



Polygastrica, 160 (Gr. polus, many ; gaster, the stomach). 



Pollen in air, 322. 



Porifera, 160. Sponges. 



Porpita, 167. A genus of Hydroida. 



Pond-stick, 81. 



Podura plumbea, 56, 175. A species of insects. 



Family Podur elide. 



Order Thysanura. 



Polishing-slate, 94. Tripoli. 



Potato disease, 136. A species of fungus. 



Powers of objectives, 55. 



Preparation of objects, 58, 61, 65, 84, 99, 156, 204, 277. 



Preservative fluids, 73. 



Preserving objects, 76. 



Primordial Utricle, 129. The bioplasmic layer of the vege- 

 table cell-wall. 



Protoplasm, 118, 128. " Physical basis of life," or the ele- 

 mentary cell material. 



Progressive force, 130 . 



Prothallium of Ferus, 126, 155. An intermediate form be- 

 tween the spore and the plant. 



Protophytes, 129. Primitive plants. 



Protozoa, 158. Simplest forms of animals. 



Professional microscope, 345. 



