738 



SCIENCE. 



[N. S. Vol. XIX. No.' 



tlie modern equids actually have such stripes, 

 but the diversity between them leads one to 

 suspect the universality of the tendency and 

 to believe that it is of recent origin. At any 

 rate, no one has a right to take it for granted 

 that primitive forms were striped. The evi- 

 dence, such as it is, is against the assumption. 



Another pure assumption is that the prim- 

 itive equoidean animals lived especially in 

 the marshes. (The unfortunate author of 

 ' The Tree Dwellers ' of course misread ' na- 

 ture ' in postulating that ' the land at that 

 time' — when five-toed horses lived! — 'was 

 almost entirely covered with water.') The 

 assumption is based on the obvious fact that 

 a four- or five-toed spreading foot is better 

 adapted for progression on soft earth than a 

 soliped, but there is no reason for confining 

 such animals to marshes. The elephants and 

 rhinoceroses are not marsh-loving animals. 



The misuse of the word horse is in natural 

 sequence to the same idea that has been car- 

 ried to an extreme in ' The Tree Dwellers ' ; 

 it is the expression of a contemptuous con- 

 descension or concession to such as are as- 

 sumed to be insufficiently educated or receptive 

 to be addressed in more ptecise language. In 

 the extreme form — disconnected sentences and 

 crude verbiage — analogous language is known 

 as ' baby tallv.' Science is scarcely food for 

 babies. Theo. Gill. 



SPECIAL ARTICLES. 



THE INFLUENCE OF CLIMATE AND SOIL ON THE 

 TRANSMITTING POWER OF SEEDS.* 



In speaking of the influence of soil and 

 climate on the transmitting power of seeds, 

 I will confine myself to certain practices which 

 seedsmen have been taught to follow through 

 long experience, as indicative of certain bo- 

 tanical facts, rather as if these facts had been 

 established by scientific study and experiment. 



Speaking first of leguminous plants, in the 

 ' Extra Early ' varieties of garden peas the de- 

 sirable form of vine is one eighteen to forty 

 inches high, and of a determinate growth, by 

 which tenn I mean a vine that before the 

 lowest and first formed pod has become too 

 large for use as green peas, has completed 



* Read before Botanical Club of Washington. 



its elongation and has its apex crowned by a 

 well-formed pod or at least one well out of 

 the blossom. The objectionable form is a 

 vine twenty-four to sixty inches in height, 

 which even when the lowest pod is fully ripe 

 is still growing having its apex covered with 

 blossoms and buds. Such plants as these last 

 are called by seedmen * wicks ' or ' offs,' and 

 a stock of ' Extra Early ' peas is valued in 

 inverse proportion to the number of such 

 plants it produces. I never have seen a 

 stock which did not occasionally produce 

 them, and in number varying with different 

 conditions of cultivation. On very rich soils, 

 or those which have been recently fertilized 

 with stable manure, there will be a great many 

 more such plants developed than on a poorer 

 soil. A stock which, when grown on a white 

 clay soil of uniform composition, will ripen 

 down very uniformly and not show more than 

 a dozen such ' offs ' to the acre, will, when 

 planted on a mucky soil or one which has 

 been enriched by fresh stable manure, give a 

 dozen ' offs ' to the square rod. 



As an illustration in detail is a case 

 when three large fields of very favorable soil 

 were planted with the same stock, two of them 

 when visited showed practically no ' offs,' nor 

 were there many to be seen in the third field, 

 except in a double row of circles, each about 

 ten feet in diameter, where piles of manure 

 had been spread, and in each of them there 

 were twelve to twenty-five bad ' offs ' more 

 than could be found on an acre of the rest 

 of the field. 



Seedsmen find that if the seed from such 

 ' off ' plants grown from good stock is planted 

 on soils favorable for the development of the 

 true type, it will produce few, very few, often 

 no more ' off ' plants than seed from plants of 

 the true tjrpe grown from the same stock; 

 but if seed from the ' off ' plants is sown on 

 soil favorable for the development of ' off ' 

 plants, they will produce more ' offs ' than 

 seeds from the true type, and this tendency to 

 produce ' off ' plants on either favorable or 

 unfavorable soil increases very rapidly with 

 the number of consecutive generations of 'off' 

 plants back of the seed in question. An illus- 

 tration was given of precisely similar results 



