282 NATURAL SCIENCE. April, 



process the phyletic metamorphosis of fruitful females is simply a 

 misuse of terms. Phyletic metamorphosis means the gradual change 

 occurring in a series of organisms of which each is the offspring of the 

 preceding. The origin of the neuter social insect from the perfect 

 female is immediate and sudden. In fact, it is not what has always 

 been understood as phyletic metamorphosis, but what is commonly 

 and universally known as sexual reproduction. 



But the problem is why is the neuter insect different from its 

 mother, instead of being similar to her ? Mr. Spencer has given the 

 obvious answer which every biologist might have been supposed to 

 know, namely, that the larva of the neuter insect is underfed, an 

 explanation which is ignored by Weismann throughout his article. 

 There are various instances which support the conclusion that in all 

 cases the peculiarities of the sterile persons are due to the conditions 

 to which the larva is exposed, but the one thoroughly-established fact 

 is that the hive-bees do actually produce perfect queens out of any 

 worker-egg or worker larva taken at random. This is sufficient proof 

 that the difference between a worker and a queen is not a constitutional 

 difference, but a difference due to the conditions of development. 

 Without at present going into the theory of biological determinants, 

 it must be admitted that peculiarities which are hereditary and to be 

 regarded as evolved are predetermined in the egg. The fact above- 

 mentioned concerning the bees, as well as other similar facts to which 

 Spencer alludes, show that the peculiarities of neuter insects are not 

 predetermined in the egg, but related to certain definite conditions of 

 development. They are not, therefore, either inherited or evolved. 

 It may be said that we do not know this for ants, but at least we know 

 nothing to the contrary. 



It follows from this that Weismann is not justified in describing 

 the differences between the worker ant and the perfect female as 

 retrogressive and progressive, implying and maintaining that these 

 differences have been gradually evolved. Among the instances of 

 retrogression he refers to are the absence of the receptaculum 

 seminis, and the reduction in the number of egg-tubes, a reduction 

 which appears in diffarent degrees in different species of ant, the 

 persistent tubes numbering 12,5,3, ^f '^^ none at all. It is clear 

 that since the larval ant has the inherent potentiality of perfect 

 generative organs, the reduction in the worker is not due to 

 degeneration but to arrested development. It may be maintained that 

 certain qualities in bullocks can be produced by the selection of bulls 

 and cows, not by the appearance of these qualities in themselves, but 

 entirely because they breed the kind of bullocks required. But no 

 one will maintain that the sterility of the bullock is one of the 

 characters that have been so produced. It makes no difference to the 

 argument that in one case the testes are removed by amputation, in 

 the other the ovaries are not fully developed. The cases are similar 

 in the predetermination of the organs in the ovum. Supposing a 



