Recent Agricultural Literature. 499 



Nine-Banded Armadillo of Texas normally and habitually produces quadruplets 

 from one ovum. These are enveloped in a common foetal membrane, and they 

 are always of the same sex. 



The Mystery of Monsters. — It is interesting to note some recent experiments 

 cm minnows which have thrown fresh light on monster-lambs, monster-calves, 

 and the other ungainly things that sometimes crop up. From_ minnow to 

 monster. What is the meaning of creatures with one eye instead of two, with 

 one ear, Vv'ith peculiar nostrils, and all that sort of thing? An old answer, 

 which has a great deal of truth in it, pointed to the fact that when an animal 

 is developing it has to some extent to retread the path of racial evolution, and 

 that if something goes wrong with the feeding of the embryo there may be what 

 are called " arrests of development." Thus the nostrils may remain externally 

 connected widi the'front of the mouth, instead of being separated off in the 

 normal fashion. When the arrest or stopi^age of development occurs and the 

 creature is Ijorn with the part unfinished, we have what is called " haro-lip " in 

 man. It is a minor monstrosity in man; it is normal in the hare! Now many 

 monstrosities are cleared up when we regard them as due to arrests in develop- 

 ment. But there are others on which this idea throws no light, and go we 

 welcome a suggestion that comes from Dr. E. I. Werber's experiments on the 

 American minnow. He subjected the developing eggs to various chemicals, such 

 as butyric acid, and he got all .sorts of monstrosities in eyes and ears, nostrils 

 and mouth, heart and fins. The chemical intrusion seemed to have a dislocating 

 and partially dissolving influence on the developing embryo, especially towards 

 the head end. Hence monstrosities. But the question naturally rises: Is 

 this more than a biological curiosity? How could any respectable embryo in 

 natural conditions become subjected to butyric acid? liut we must be patient. 

 Part of the food of higher animals consists of carbohydrates, such as starch and 

 sugar; when the chemical routine that goes on in the body in connection with 

 carbohydrates goes " agley " in a certain way, one of the results of the dis- 

 turl)ance is the formation of butyric acid. If this butyric acid was formed in 

 the l)ody of the pregnant mother it might affect the unborn offspring, her close 

 partner, and might produce monstrosities. This seems to us to be a big contii- 

 bution towards the solution of the mystery of monsters. 



The Control of Sex comes Nearer. — It maj' be said with fairness, we think, 

 that almost all the recent work on the determination of sex in birds and 

 .mammals points to the conclusion that the sex is settled when the egg-cell is 

 fertilized, if not before that. Some very careful investigations on pigeons by 

 Prof. Oscar Riddle force one to think. He makes it practically certain that 

 pigeons lay two kinds of eggs, which differ fiom one another in the rate or 

 intensity of their chemical processes. One kind of egg has a comparatively low 

 storage capacity, a high oxidizing cajjacity, and a relatively higher intensity 

 of chemical changes (or metabolism) ; and this type of egg develops into a cock 

 bird. The contrasted type of egg, with' higher storage caj^acity, relatively less 

 intense metabolism, lower percentage of water, higher total percentage of fat 

 and phosphorus, and greater energy-value in the yolk (as determined by the 

 calorimeter), develops into a hen bird. It is very interesting to find also that 

 an intermediate type of egg, produced early in the season, will develop into a 

 female bird with a good many masculine features about her. Moreover, chemical 

 analyses of the blood of full-g'own male and female pigeons show that the con- 

 stitutional differences which can be detected in the two kinds of ova persist 

 in adult life. These experiments furnish a corroboration of the thesis worked 

 out by Geddes and Thomson in The Evolution of Sex as far back as 1889, that 

 temaleness is a.ssociated with a relative preponderance of constructive, or up- 

 building or anabolic physiological processes; and conversely for maleness. In 

 short, the sexes differ fundamentally in their physiological gearing, in the rate 

 or intensity of particular vital processes. 



(2) Versla(je7i en Mededeelingcn van de Direktie van den Landbouw in Neder- 

 land, No. 1 ot 1920, deals with the damage done to Agriculture, Horticulture, 

 and Forestry by game and injurious animals. Figures are given of the estimatecl 

 damage caused in the different provinces, and methods of combating the pests 

 dealt with. The greatest damage is said to be caused l)y birds, especially 

 sparrows, crows, and pigeons. The report recommends that, where necessary, 

 land-owners or game licencees be ijistructed to eradicate stich injurious game 

 within a certain period, after which, if not sufficiently reduced, the State, in 

 consultation with Provincial Commissions, will employ persons to complete the 

 work. 



