114 TRANSACTIONS, NATURAL HISTORY SOCIETY OF GLASGOW. 



In like manner the pod of Scorphirus subvillosus 

 has a curious resemblance to a centipede, and that 

 of S'. vermiculatus to a worm or caterpillar. The 

 long hanging pods of Trichosanthes anguina, as 

 its name indicates, look very much like snakes. 

 Bisernda pelecinus resembles a centipede. According 

 to Lubbock the seeds of Abitis precatoi'iiis, Martynia 

 diandra, Jatropha, and Ricinus mimic beetles, while 

 several lupines have spider-like seeds. The advantage 

 of the mimicry in the rosary-bean (Abrus) is easily 

 understood. The beans are bright scarlet with a 

 black glossy patch. When the pod dehisces they 

 are exposed to view, and attract, we shall suppose, 

 an insectivorous bird which mistakes them for a 

 particular kind of beetle. After carrying the bean 

 some distance the bird discovers its error, drops the 

 seed, and thus gratuitously disperses the seeds of 

 Abi'us. Other mimetic seeds may attain their object 

 in the same way. Very possibly this explanation 

 applies to the seed of the common British cow-wheat 

 {Melampyrum pratense), which presents a strong 

 resemblance to the larva of an insect. 



The advantages of dispersion through the agency 

 of birds are: (1) The possibility of transport across 

 mountain-ranges and arms of the sea, which would 

 prove effectual barriers to wind-borne seeds unless 

 of infinitesimally small dimensions. (2) The delivery 

 of the seeds in particular situations corresponding 

 to the habitat of the plant. (3) This mode is 

 preferable to wind agency where the number of 

 individuals composing the species is limited, since 

 fewer seeds will be lost or destroyed. 



8. Animal Agency.— While succulent fruits in 

 general are adapted for dispersion by birds, this 

 does not seem to be universally the case. Many of 

 the Cucurbitacese have large succulent fruits, but are 

 indifferently adapted to bird-dispersion. The size, 

 position, and colour of these gourd-like fruits are 

 unfavourable to this mode of dissemination, and point 

 rather to dispersion by large quadrupeds, accustomed 



