L Y At 



[269] 



MAC 



mon elm consisted as follows : Of 

 1039 parts, 1027'904 water and 

 volatile matter, 9-240 acetite of 

 potash, 1-060 vegetable matter, 

 0-796 carbonate of lime. 

 LYMPHA'TICS. Minute vessels per- 

 vading every part of tbe body, 

 absorbing and conveying the ab- 

 sorbed matter into the thoracic 

 duct, to be afterwards conveyed 



into the blood. The lymphatics 

 are supplied within with valves, 

 and without with glands. 

 LY'EATE. (from lyra, a harp, Lat.) 

 Lyre-shaped; a term applied to 

 leaves divided transversely into 

 several segments, the segments 

 gradually increasing in size as they 

 approach the extremity of the 

 leaf. 



M 



MAC'ACUS. The fossil monkey, of 

 which two species are described by 

 Professor Owen, namely, M. 

 Eocoenus, and M. Rhesus. " Cuvier 

 says, our great comparative anato- 

 mist had met with no evidence of 

 any species more highly organized 

 than a bear or a bat, in the fossili- 

 ferous strata which formed the 

 theatre of animal life anterior to 

 the record of the human race. I 

 have been so fortunate, in my re- 

 searches of the fossil mammalia of 

 Great Britain, as to determine not 

 only the remains of extinct pachy- 

 dermal animals (Lophiodon and 

 Hyracotherium) in the Eocene 

 beds called the London clay, but, 

 likewise of a Quadrumane, or mon- 

 key, in a sandy stratum of the 

 same formation." 



MACHAI'HODUS. The name assigned 

 by Dr. Kaup to an extinct genus 

 of carnivorous mammalia, distin- 

 guished by their falciform teeth, 

 and found in the newer tertiary 

 deposits of Italy, Germany, France, 

 and Great Britain. Prof. Owen, in 

 describing one species, the M. La- 

 tidens, says, it was a feline animal 

 as large as the tiger, and, to judge 

 by its instruments of destruction, 

 of great ferocity. The canines 

 curved backwards, in form like a 

 pruning knife, having the greater 

 part of the compressed crown pro- 



vided with a double-cutting edge of 

 serrated enamel ; that on the con- 

 cave margin being continued to the 

 base ; the convex margin becoming 

 thicker there, like the back of a 

 knife, to give strength. Thus each 

 movement of the jaw with a tooth 

 thus formed, combined the power 

 of the knife and saw. 



MACHAI'KODTTS. An extinct animal 

 of the order Mammalia, referrible 

 to the Miocene period, and allied 

 to the bear. 



MACI'GNO. The Italian word for a 

 kind of stone, a siliceous sandstone 

 sometimes containing calcareous 

 grains, &c. Macigna pietra, a very 

 hard stone ; an eocene rock of 

 Italy. 



MA'CLE. The Hohl spath of Werner ; 

 Hollow spar of Jameson. Made 

 occurs only in crystals, the form of 

 which is a four-sided prism. But 

 each crystal, when viewed at its 

 extremities, or on a transverse sec- 

 tion, is obviously composed of two 

 very different substances ; and its 

 general appearance is that of a 

 black prism, passing longitudinally 

 through the axis of another prism, 

 which is whitish. These crystals, 

 often long, are sometimes very 

 minute; in some instances their 

 edges are rounded. The crystals 

 of Made present a considerable 

 number of natural joints, which 



