HUMAN RESEMBLANCES TO LOWER LIFE. 15 



Passing backwards in animal history, we discover that the 

 true story of living beings is often to be compiled by the aid of 

 development alone. In truth, the investigation of tails as they are, 

 reveals very little about tails as they were. We may safely apprehend 

 that the human tail represents a degenerate appendage. It remains 

 for development to show us that our supposition implies a fact. If 

 we trace human individual history backwards to a period very early 

 in the development of our frame, we shall find that the extremity of 

 the spine is not only a very prominent feature in human anatomy, 

 but projects distinctly beyond the lower extremities. The human 

 tail in an early stage of our development, is, in fact, twice as long as 

 the legs. At the corresponding period in the development of the 

 highest apes, the tail is equally prominent. As development advances, 

 however, the caudal extremity begins to decline, and comes to assume 

 its human characters, or rather to assume these features which, in 

 this respect, man shares with the higher apes. Only in rare cases, 

 does the "tail" persist in its early condition, and in such instances 

 the individual is born in possession of an external rudiment of a 

 caudal appendage. In the degraded "tail" of normal humanity, 

 the rudiment of the " extensor " muscle of the tail is, however, 

 still to be found ; this muscle linking us to the lower stages, in 

 which the tail-movements are a characteristic feature of life. Curi- 

 ously enough, at the tip of the human tail, there is known to exist 

 a very singular structure, the exact nature of which was for long 

 doubtful. But as this structure was believed to correspond to the 

 tail-bloodvessel in a modified condition, search was made for a 

 similar structure in lower life, with the result that in the cat and 

 in a Macaque monkey, a similar body was found, although in these 

 animals it was not situated as in man, at the extremity of the appen- 

 dage. The occurrence of such a body in a true and well-developed 

 tail shows how clearly the terminal point of man's spine falls within 

 the category of " caudal" structures. 



One of the most striking features of human anatomy leads us 

 to investigate very briefly the structure of the intestine, which, as 

 every reader knows, is simply the digestive tube continued onwards 

 from the stomach. The digestive system of any animal may in 

 fact be described as a tube, whereof the stomach itself is merely 

 a distended part. In most animals, the intestine can be divided 

 into a " small " and " large " portion ; the former becoming con- 

 tinuous with the latter. At the junction of the small and large 

 intestine of humanity, there is found a pocket-like portion, forming, 

 in fact, the first part of the large intestine, named the caecum. 

 Attached to and opening from this pocket, is a small tubular appen- 

 dage, which, at first sight, suggests a structure of rudimentary and use- 

 less kind. That the coecum itself is of rudimentary kind in man, is 



