ON BIOLOGY. 83 



structure. It is dense and strong, contains a large quan- 

 tity of yellow elastic tissue arranged iufasciculi, as in the 

 tendon of a muscle." (Sutton.) 



Now the ambiens is another remarkable muscle of the 

 thigh in birds which has very much excited the interest 

 of morphologists, and in the adult ostrich it is seen to be 

 connected by fibrous tissue whh our ligamentum teres. In 

 the chick of th-; ostrich this fibrous tissue is seen to be a 

 muscular slip, and Sutton believes, on the best of evi- 

 dence, that that muscular slip and the ambiens repre- 

 sent the mammalian pectineus muscle. He is then en- 

 abled to trace its varying relations and conditions from 

 the lizard Sphenodon to man, proving most conclusively 

 its true nature as I have just given it. The account, or 

 rather chapter, is concluded by his saying: 



"There is no ligament in the body which can boast 

 such an extensive literature, or has exercised more the 

 ingenuity of physiologists and surgeons than the one we 

 have been considering." * * * * 



"Teleologists like Paley have been enraptured with 

 this structure, and anatomists have ascribed to it won- 

 derful mechanical resistance and uses. Alas! in this, as 

 in so many like cases, morphology demands for it a low 

 level, and determines it to be a vestigial and practically 

 useless ligament. In this sense teleology Is as poetry, but 

 morphology as plain history." 



These two very excellent illustrative examples will 

 serve to show the direction of the lines along which mor- 

 phology of the future must of necessity progress; and the 

 advance of the science of physiology will be quite in keep- 

 ing with it. And, it may be said, inasmuch as the first 

 stands for all those phenomena of living organisms which 

 relate to form, and ihe latter for all those which relate to 

 action, that however independently these two lines of in- 

 quiry may be progressing now, the day must assuredly 

 arrive when biologists will appreciate that, perhaps, 

 after all, but one outcome is common to the two, and it 

 is indicated by the same molecular processes. Foster 

 has recently said: 



"The problems of physiology may in a broad sense be 

 spoken of as threefold. (1) On the one hand, we have to 

 search the laws according to which the complex, un- 

 stable food is transmuted into the still more complex and 

 still more unstable living flesh, and the laws according 

 to which this living substance breaks down into simple, 

 stable waste products, void or nearly void of energy. (2) 

 On the other hand, we have to determine the laws ac- 



