Wilder.] 182 [Aprils, 



Definition. The syntropical relation between parts upon the 

 same side of the vertico-lateral plane. 



Example. Two thoracic ribs or vertebrae. 



Eemark. Since this is the kind of syntropy which is most appar- 

 ent and most commonly treated of, it may be allowable to use the 

 shorter term syntropy for the longer one when no misunderstanding 

 can arise. 



Platesyntropy (tiIutoc, breadth). 



Actinolorjy (serial, correlated, etc.), Miv., 278, 118. — Latiserial ho- 

 mology, Wild., 58, Lect. 1. 



Definition. The morphotropical relation between parts upon the 

 same side of the vertico-longal plane. 



Examples. Brachium and cubitum ; two right maxillary teeth ; 

 two dermal scuta of right side of armadillo. 



Hypsesyntropy (y/og, height). 



Vertiserial homology, Wild., 58, Lect. 1. 



(Other synonyms will be included under Pseudantitropy). 



Definition. The syntropical relation between parts upon one 

 side of the longo-lateral plane, which, in vertebrates at least, I am in- 

 clined to believe should not bisect the body of a single individual into 

 a dorsal and a ventral region, but should pass between two individuals 

 of opposite sexes. 



Examples. A rib and its cartilage ; two muscular bundles of the 

 same muscular segment (myocomma, Owen; myotome, Good sir). 



Kemark. Probably no objection exists to giving the name pro- 

 posed to the relation between a rib and its cartilage ; for both lie ven- 

 trad of the vertebral axis ; but so general is the impression that the 

 vertebrate body presents a "dorso-ventral symmetry" (Macl., 23, 671; 

 Pittard, 293, 851; Wyman, 55,253; Spencer, 299,2,186; Coues, 

 70, 150), that it is not easy to show that this relation between organs 

 lying upon opposite sides of the vertebral axis is really one of syn- 

 tropy rather than of antitropy; yet I am convinced that this "sym- 

 metry" which is so striking in some fishes, is one of appearance 

 chiefly and affects the external form only; certain it is that nothing 



