1905-1906.] The Great Gulf . 259 



who lived A.D. 1707 to 1778, that we are indebted for the first 

 serious effort to cover this region of knowledge. His system 

 was no doubt a highly artificial one, but it was unquestionably 

 the foundation of that enormous mass of knowledge which we 

 now possess in botanical and biological science. His system 

 was, as I have said, an artificial one, but Linnaeus quite under- 

 stood and grasped the fact impressed on him by his study of 

 botany, that there existed a natural system of classification of 

 plants, based upon their mutual relationships to one another. 



From the study of this natural system of classification in 

 plant and animal life grew one of the most brilliant theories 

 ever propounded, and one which has completely revolutionised 

 the science of biology. In studying the relationships of plants 

 and animals, it was soon discovered that these were in the 

 form of a ladder, the first step of which consisted of life in a 

 very lowly form — a single independent cell; while, as one 

 mounted upwards, the steps increased in complexity and 

 variety of form till one reached the top. This fact appears to 

 have suggested to the minds of philosophers the great theory 

 of evolution. Broadly stated, the theory avers that such a 

 ladder with its numerous steps did not always exist, but that 

 the first life known on our planet consisted of the low forms 

 only, and that from these the more complex forms were 

 gradually evolved step by step. This theory has been a hard 

 one to prove, or even to maintain. The first great upholders 

 of it— Darwin (a.d. 1809-1882) and Wallace (born in 1822) 

 — were met with a perfect storm of opposition from all sorts 

 and descriptions of people. Whatever truth there may be in 

 the theory, however, one important point has been brought to 

 light in the course of its investigation. This point is, that 

 there are a good many steps awanting in the ladder of life as 

 we know it at the present day, which recalls to mind what 

 was for a time a most burning question — that, namely, of the 

 missing link between man and the other animals. It is such 

 a missing link, or more than one, in fact a great hiatus, be- 

 tween two sections of the vegetable kingdom, that forms the 

 subject of this paper. 



In classifying the vegetable kingdom, we find that it first 

 of all naturally divides into two great groups of plants, named 

 (1) the Phanerogams, or plants with more or less conspicuous 

 flowers, and (2) the Cryptogams, or plants devoid of flowers, — 



