17 



ages, as it' tlicy t'dniird a c-liain in cNdliit inn. Imt it will separate, 

 link after link, in like manner, und'.'r the irlanee of a scientist. 



A knowledge of evolution followed the doniestieation of animals 

 centuries ai^o Iml how an<l when' it lakes place is a subjei't of mod- 

 ern investigation. And we do not know how or wliere it has taken 

 place, except as a result of observation and experiment. The theory 

 of evohition does not account for anytiiing. though an established 

 fact may b'.i consistent with the theory. .VII biological knowledge 

 follows the discovery of the hard and soft parts of the anatomy of 

 living animals, but among extinct fossil animals it is only to be in- 

 ferred after a full knowledge of the lianl ])arts found preserved. 

 And .liinricofriiiiis is a good genus with which to make an illustra- 

 tion. We know that some crinoitls, as Encdhijihirriiiux. were per- 

 manently attached by roots that penetrate the mud. at the bed of 

 the sea. like a forest tree iienetrates the soil on land, that others, 

 like . 1 //o(/(f(/()r/-///H.s- attached roots to foreign objects, or were free, 

 like I'lii-iiucriiiiis, and though floaters could attach themselves by 

 coiling tiie tapering ends of their columns around other objects; but 

 we do not know to which of these divisions .{(/(ii'/i-ocr/ii/is belonged. 

 We know that the columns in some crinoids were square, others 

 pentagonal and others round and that the column of A<i(iric<)crliiii>t 

 was round: but we do not know what significance, if any. in the line 

 of development, is to be attached to the form of the column, its 

 structure, or the sha])e of the columnar canal, We know nothing 

 of the internal anatomy of the calyx or head of Ai/dfirofriniis and 

 cannot trace the source of the genus, if it is to be found, in known 

 species of earlier age or tind tlie evidenci's of its sur\ival. if it did 

 survive, in later crinoidal forms. 



We know by the three basals. absence of subradials. ])resence of 

 jirimary radials and regular interradials. t]iat .{iidricofriiiiix must be 

 classed, in the family ActiiKirrinithi'. which is established on the 

 hard jjarts of the fossilized tests, and which has had no representa- 

 tive, so far as discoveries have progressed, since the Subcarbonifer- 

 ous age. They ante-date the Carboniferous laeriod. An old Eng- 

 lish naturalist said. '"Providence maintains and continues every 

 created siiecies: and we have as much assurance, that no races of ani- 

 mals will any more cease, while the earth remaineth. than seed time and 

 harvest, cold and heat, summer and winter, day and night. " But 

 we have, on the contrary, every assurance that observation, discoy- 



