HIS ON THE VASCULAR SYSTEM. 353 



"like the four corners of a letter." Yet this wonderful 

 " envelope theory " of the vertebrate limbs is surpassed by 

 the " waste-rag theory " (Hollen-lappen Theorie) which His 

 gives of the origin of the rudimentary organs : " Organs 

 (like the hypophysis and the thyroid gland) to which no 

 physiological part has yet been assigned, are embryonic 

 remnants, comparable to the clippings, which in the cutting 

 of a dress cannot be entirely avoided, even by the most 

 economical use of the material " (!). Nature, therefore, in 

 cutting out, throws the superfluous rags of tissue into the 

 waste heap. Had our skull-less ancestors of the Silurian 

 age had any presentiment of such aberrations of intellect 

 of their too speculative human descendants, they w T ould 

 certainly have preferred relinquishing possession of the 

 hypobranchial groove on the gill-body, instead of trans- 

 mitting it to the extant Amphioxus, and of leaving a 

 remnant of it to us, in the equally unsightly as useless 

 thyroid gland. (Cf p. 336). 



It will probably be thought that the ontogenetic " dis- 

 coveries " of His, which appear in a doubly comical light in 

 consequence of the accompanying display of mathematical 

 calculations, can only have occasioned momentary amuse- 

 ment in critical scientific circles. Far from it ! Immedi- 

 ately after their appearance, they were not only much 

 praised as the beginning of a new " mechanical " era in 

 Ontogeny, but they have even yet numerous admirers and 

 adherents, who seek to spread the scientific errors of His as 

 far as possible. On this account, I have felt myself obliged 

 to point out emphatically the complete falsity of these 

 views. The vascular system affords especial occasion for 

 £his ; for among the most important advances which Hiq 



