140 



The nematode appeared to be Aphelenchus pyri, Bastian, 

 a species originally found in decaying pears. Its presence in 

 potato tubers, notwithstanding the amount of injury effected, 

 does not necessarily prove the nematode to be a true parasite ; it 

 is at most a wound-parasite, gaining an entrance into the tuber 

 through the minute opening formed by the decay of the tissue 

 enclosed by the vascular ring at the point of its entrance into the 



tuber. 



Two tubers infected at the point indicated above, by covering 



the scar with slime containing eelworms obtained from a diseased 



tuber, were placed under a bell-jar, and kept in the dark at an 



average temperature of 65° F. After ten days one of the tubers 



was cut open and revealed a cavity about one inch in diameter 



filled with slime containing myriads of eelworms. The second 



tuber was allowed to remain for a month when the internal cavity 



was found to have reached the limit of its extension, that is up to 

 the vascular ring. 



In a second experiment the " eyes " of two tubers were covered 



with^ nematode - bearing slime, and afterwards placed under 



conditions similar to those described in the previous experiment. 



After remaining for a month the nematodes had not effected an 



entry into the tuber, although in some instances small " sprouts " 



had pushed from the "eyes" through the slime. This experiment 



may be taken to prove that the nematodes cannot effect an entry 



through an unwounded surface, even when the tissue is quite 

 young. 



No trace of bacteria or fungi was found in the slime. 



The potatoes were purchased at the Brentford market, hence 

 their source of origin is unknown, as is also the nature of the soil in 

 which they were grown, or the kind of manure used, &c. Judging 

 trom the large percentage of hollow tubers present in the small 

 quantity purchased, it would appear that a local epidemic, caused 

 by nematodes, had existed where the potatoes were grown. • 



tw^i^T acco i unt is not intended to convey the impression 

 r^J Voices are due to eelworms. Potatoes are often 



SSSiaSv w T c T VUte } y , hollow ed. out by centipedes, more 

 X? is la £S lU l r lcM,US - In 8Uch instances however an 



the r w!v fnto fi? ? * by - COIUmen "ng at the surface and eating 

 their way into the interior of the t.n W 



G. M. 



Botanical Magazine for February.-The plants fisured are 



ihmanma annul ntr, xx i ^i . piants ngureu die 



litrmTsduH^Mivil • „" Vodonopsis convolvulacea, Kurz, 

 Z?mthUnooti h ^fini Po^7to concolor, Rolfe, and Larix 

 sS*hi£^« 1 ? X*hmannia is a handsome Wge-flowered 



cXvattnT ryetsVoT M^t Chin * intr ° dUCed in S 

 is not quite hardv n"i «. \ MeB8r3 * James Veitch & Son8 ' Xt 



Oodonop 



garuen plant when treated as a biennial. 



are alfthe other " spSof 5,***™ of , Eastern Asia > as indee(1 

 now known. This 8 D ecip« g6nU9 ' ° f Which t^nty-two are 



terised by having the calvv inK gS i t0 the 8ma11 8ection charaC_ 



The Kew plant 



