122 GLOSSARY. 



Rete vasculo'sum tes'tis (L. vascular net of the testicle). The 



network of tubes into which the vasa recta of the testicles 



are gathered 

 Reticular (L. rete, a net). Net-like; disposed like the 



threads of a net. 

 Reti'culum (L. a little net). The name given to the web of 



delicate connective tissue between the nervous elements 



in the spinal cord and some parts of the brain. 

 Re'tifonn (L. rete, a net; forma, shape). Net-shaped; like 



a network. 

 Retina (L. rete, a net). The delicate expansion of the optic 



nerve which forms the inner coat of the eye. 

 Retina'cula(L. restraining bands). Bands which serve to hold 



the tendons close to the bones in such joints as those of 



the wrist, ankle, &c. Also the ridge which extends for 



some distance round the ileo-ccecal valve. 

 Retractor (L. retracto, to draw back). A name given to those 



muscles which by their contraction withdraw the parts to 



which they are attached, as the retractor muscles which 



withdraw the foot in the Lamellibranchiata. 

 Retrac'tor bul'bi (L. retractor of the bulb). Another name for 



the musculus choanoides of the eye which see. 

 Retrahens auri'culam (L. retractor of the auricle). One of the 



muscles of the auricle of the ear. 

 Rhabdocoela (Gr. rhabdos, a rod, line ; koilia, the bowels). 



Applied to those Turbellaria which have a straight digestive 



cavity. 

 Rha'chis (Gr. a spine, ridge). A cord of protoplasm formed 



in the ovary of the Nematoidea, round which the ova are 



developed. 

 Rhamphorhyn'clms (Gr. rhatnphos, a beak ; rhunchos, a snoutX 



A genus of the Pterosauria having the jaws produced 



into toothless beaks. 

 Rhe'idae (Hhea, the American ostrich). A group of birds which 



comprises the American ostriches. 

 Rhl'nal pro'cesses (Gr. rhis, rhinos, the nose). Two slender 



cartilages in the chondro-cranium of the frog. 

 Rhinence'phalon (Gr. r/it's, rhinos, the nose ; enkephalon, the 



brain). A term applied to the olfactory lobes of the brain. 

 Rhizocl'phala (Gr. rhiza, a root; kephale, the head). A group 



of small parasitic Crustacea. 

 Rhi'zoid (Gr. rhiza, a root ; cidos, shape). A term applied to 



the rootlets of Chara and similar plants. 



