1907 Reviews. 367 



he would probably have no idea of the large extent of the variation in 

 the Tunicata, and would be apt in reading the specific descriptions to 

 look upon the characters given as absolutely fixed, little or nothing 



being said about variation. 



H. J. Buchanan Woi,i,as7on. 



NOTES. 



BOTANY. 



Vitality of Seeds swallowed by Animals. 



It is well known that the manure of horses fed on oats frequently 

 contains whole seeds of that species, but it may not be so well known 

 that these can retain their powers of germination. I have seen a number 

 of examples of this of late, and, indeed, a garden plot that was manured 

 in this way would, if left to itself, have produced a fair crop of oats. 



Some horse manure was obtained in 1906 for the growth of Mucor, as 

 it forms one of the best culture media for that fungus. After the Mucor 

 died off it was succeeded by another fungus — a species of Coprinus. 

 This in turn was followed by still another fungus— a species of Ascobolus. 

 Of eleven flowering plants which made their appearance four were Oat, 

 five Perennial Ryegrass, one Soft Brome Grass, one Holcus lanalus, and 

 one other species was accidentally destroyed before flowering. The seeds 

 of all these grasses were doubtless present in the haj on which the horse 

 was fed. As the seeds of grasses and cereals take up water very slowly, 

 continuing to absorb it for forty-eight hours it would seem that they 

 were not submitted long enough to the action of the digestive ferments 

 to receive serious injury. 



During the spring of this year a number of seeds of Ivy were isolated 

 from the excrement of birds— either Blackbirds or Thrushes. Sixteen 

 seeds in all were planted on 29th April, and on the 28th June ten had 

 germinated. Succulent fruits, such as Hawthorn, Bramble, and Goose- 

 berry, usually have their seeds distributed by birds, but in that case the 

 seed is protected by a hard stone or seed-coat so that it is not crushed in 

 the bird's gizzard and is scarcely acted on by the digestive juices. In 

 the case of the Ivy, however, the seed is surrounded by a thin membrane 

 only, through which one would suppose the digestive ferments could 

 easily pass. It is certainly rather curious that the seeds are not ground 

 up, as the} 7 are quite soft. 



The berries of the Ivy are poisonous to cattle, though it does not neces- 

 sarily follow that they have a like effect on birds. As in the case of Yew, 

 it is possible that the poisonous principle is located in the seed and 

 not in the succulent part enclosing it, and, if that be so, it might 

 account for the fact that the birds survive, the seeds passing through the 



intestine intact. 



J. Adams. 

 Royal College of Science, Dublin. 



