COL 



[99] 



COM 



colon commences in the crecum, 

 and terminates in the rectum. 



COLO'PHONITE. (from /co\o0oWa, Gr. 



resin.) So named from its resin 

 colour. The grenat resinite of 

 Haiiy. Found near Pitigliano, in 

 Italy, and in Norway. A brown 

 or red variety of dodecahedral 

 garnet, having a resino-adamantine 

 lustre ; it is chiefly found at 

 Arendal, in Norway. It consists 

 of silica 37, alumina 13-6, lime 29, 

 oxide of iron 7'4, magnesia 6 f 5, 

 oxide of manganese 4*7, oxide of 

 titanium 0-5, water I/O. Specific 

 gravity 3*5. 



COLT/MBITE. A mineral ore, the ore 

 of columbium. 



COLU'MBIUM. A metal first discovered 

 in 1801 by Mr. Hatchett in a 

 mineral brought from North Ameri- 

 ca, from which it received its 

 name. It is of a dark grey colour, 

 very dense, and difficult of fusion. 

 This metal takes fire when heated 

 in contact with air, and burns into 

 columbic acid, which consists of 

 85 columbium and 24 oxygen. 



COLTJMBE'LLA. A genus of spiral 

 univalve shells; they are thick, 

 oval or angular; spire shut, aperture 

 long and narrow, terminating in 

 an anterior canal; the outer lip 

 is thick and dentated, inner lip 

 crenulated. The C. sulcata is 

 recorded from the Crag of Walton 

 on Naze. Lyceit. 



COLUME'LIA. (Lat.) ^Inconchology, 

 the upright pillar in the centre of 

 most of the univalve shells. 



CO'LTJMN. In botany the central point 

 of union of the partitions of the 

 seed-vessel, (that is in a capsule 

 containing many cells) to which 

 the seeds are usually attached. 



COLTJ'MNAR. Formed in columns ; 

 having the form of columns ; 

 having the circumference always 

 circular, but the thickness indeter- 

 minate. In this last character 

 columnar differs from cylindrical; 



cylindrical bodies being equally 

 thick throughout. 



CO'MATE. (comatus, Lat.) Hairy. In 

 entomology, having the upper part 

 of the head, or vertex, alone covered 

 with long hairs. 



COMA.'TTJLA. An existing genus of 

 radiaria of the family of Crinoidea. 

 The comatula presents a conformity 

 of structure with that of the pen- 

 tacrinite, almost perfect in every 

 essential part, except that the 

 column is either wanting, or at 

 least reduced to a single plate. 

 Peron states that the comatula 

 suspends itself by its side arms 

 from fuci, and in this position 

 watches for its prey, and obtains it 

 by its spreading arms and fingers. 

 Miller. Four species of the genus 

 comatula discovered at Solenhofen, 

 in the oolite, have been determined 

 by Goldfuss, namely, C. filiformis, 

 C. pectinata, C. piunata, and C. 

 tenella. 



COMB. ] These words, thus differently 



COMBE. > written, appear to be of 



COOMB. ) Saxon origin. Eay gives 

 the second as a south and east 

 country word, and defines it to be 

 a valley, " vallis utrinque collibus 

 insita." Lyell states it to be a 

 provincial name for a valley on the 

 declivity of a hill, and which is 

 generally without water. Buckland 

 says, "the term Combe is usually 

 applied to that unwatered portion 

 of a valley, which forms its con- 

 tinuation beyond, and above the 

 most elevated spring that issues 

 into it; at this point, or spring- 

 head, the valley ends and the combe 

 begins." A narrow undulating 

 ravine. 



COMBU'STION. (combustion, Fr. com- 

 bmtione, It.) Consumption by fire; 

 the disengagement of light and heat 

 which accompanies chemical com- 

 bination. 



CO'MMISSURE. (commissure*, Lat.) A 

 joint, seam, or suture. 



