24 xomi:nx'I.atuuk. 



29. 



In order tliat we niav be able to distinguish surfaces exact- 

 ly, we must attend to the following expressions. 



Linear {I'mcarl^ § 16.), is, as was formerly remarked, a 

 surface uhicli preserves the same small dimensions through- 

 out, and is every where about the breadth of a geometrical 

 line. 



Orbicular {orh'icidar'is)^ is a surface which has pretty near- 

 ly the form of a circle. If it deviates more or less from the 

 circular form, it is called roundish^ {sid)roiundus). The term 

 rounded {rotundatus) is also used, Avhen one part of the cir- 

 cumference approaches to the round form. 



Ovate {ovaiu.s), is when a surface is rounded at the base, 

 but tapers towards the apex, and when its length is a little 

 greater than its l)readth. 



Elliptical, or oval, {elUpt'icus, oval'is)^ is when the length 

 of a surface exceeds its breadth twice or thrice, and it is 

 cquall}' rounded at both ends. (Tab. VII. Fig. 6.) 



Oblong {ohlongus), is a surface, the length of which ex- 

 ceeds the breadth more than three times, and which has its 

 ends variously defined. (Tab. VIII. Fig. 2. 5.) 



Lanceolate {lanceolatus)^ is a surface which tapers gradual- 

 ly towards its apex, and is of considerable length. 



Spathulate {spatlndatu.s), when a surface is rounded at the 

 apex, and tapers towards the base. 



W^edge-shaped {amcaUis^ or cuneiformls), denotes proper- 

 ly a surface which terminates in a right line at the apex, and 

 tapers towards the base. It is usual also, without regarding 

 the apex, to designate this tapering alone, under the name of 

 the xvedgc-shapcd. 



Tongue-shaped {lingulatu.s)^ or band-shaped {Ugulutus)^ 

 denotes a surface of some length, with blunt ends, and paral- 

 lel sides. 



Sword-shaped {cnsifoi'mi.s), is an oblong surface, one mar- 

 gin of which is hollowed, and the opposite one is elevated. 



Sickle-shaped (Jalcatns)^ is a curved surface, one part of 

 which remains straight. 



