294 GLOSSARY. 



Stolons. In zoology connecting processes of the ccenosarc, &c. 



Stomatodcndra. The branches of the tree-like mass of the syn- 

 dendrium of the Khizostomidae. 



Strobila. A stage in the development of certain Hydrozoa. 



Stroma. The bed in which a tissue or organ originates. 



Struggle for life. Mr. Darwin uses "this term in a large and 

 metaphorical sense, including dependence of one being on 

 another, and including (which is more important) not only the 

 life of the individual, but success in leaving progeny." 



Swim-bladder, air-bladder, or sound. An organ filled with air, 

 placed under the spine in fishes. It is the homologue of the 

 lungs. 



Symmely. A monstrosity, as when two or more parts are joined 

 together. 



Symmorpks. Parts having the same form. 



Synangium. The bulbous end of the aortic trunk in Amphibia. 



Synapticula. " Transverse props " between the septa in a coral- 

 lite. 



Syncytium. The ectoderm of certain Spongia in which the nuclei 

 show no trace of being contained in cells. 



Syndendrium. The complex tree-like mass dependent from the 

 umbrella of the Rhizostomidse. 



Synthetic. When a combination of characters occur which nor- 

 mally find their expression in other groups. 



Syrinx. The lower larynx, the chief organ of the voice in birds. 



Syzygium. An unmovable suture. 



Tabula. Horizontal plates in the thecae of certain corallites. 



Tarsus. In mammals and some other vertebrates the small 

 bones of the foot ; in insects the small consecutive joints end- 

 ing the legs. 



Taxonomy. " The principle of classification." 



Tectology. The science of the laws of the grouping of parts 

 which go to make up an individual. 



Tectrices or wing-coverts. The small feathers on the forearm 

 are the lesser, and those over the quill-feathers are the greater 

 coverts tec-trices primes and tectrices secundce respectively. 



Tegmina. The upper wings of the Orthoptera and homopterous 

 Hemiptera ; they are uniform in texture, and have no lining 

 membrane beneath. 



