398 



ill the small crui) I'lii^f'l in l!'l(;, attaiiird the Mei.iiht of o Ihs. :> oz. 

 ( loiiv! ui'ainiucs). The incmilaritv of the tiil)('rs may he considor- 

 (m1 as imperfect lii'aiicliiiii;- : Imt no liraiicliiii,!;- of tlie slender part, 

 the stalk-like [lart. of the tuherons root <.(curs. — onl.v of the swollen 

 ajncal i)art. 



On tlie n|)|ier part of IMate S are ti,i:iiivs of three Indian races, 

 which in l!M(i had their Lirowth interfered with: as a conse(|uenco 

 of which the I'oots appeal' comparatively poor: but the lial.it is 

 iie\crtheless truly represente(|. The uppermost of the three is a 

 ('hitta.uonu- race, received from India in 1!M;! under the name of 

 Poi-a alu or "Oar tuher." In its lii'st year in Singapore it re- 

 turned so heavilv from a small hed as to yield at the rate of 21,851 

 Ihs. per acre, the numlier of tuhers on a plant heiiiu on the avera.u'e 

 twenty-live (\ide this Bulletin, pp. ;!ii-.^-;;(i;!. ) The raci' has roots 

 armed freely with rather small thorns. 



I'nder I'ora alu on jdate N are represented, as Xo. -^'.Ki, tin,' 

 (idiadu nf Herar. and. as No. -^ilS. the China alu of Jorliat in 

 Assam. This latter ;.;(»es unarme(l or almost so: hut (ioradu has 

 I(ui.l:' forinidahle thorns on its protectixc roots, which overlie the 

 tuherons roots. In these three Indian races the length of the tuber 

 bears a fairly constant relation to the diameter. Their tuhers are 

 shorter and rounder than those of the trio 290, 276 and 292. 



The rest of the races to be referred to, may be arranired con- 

 veniently in a series eommeneing with those whose tubers are re- 

 latively small and ending with those that are the largest. No. 278 

 figured at the top of i)late 9 leads thus to Xo. 28U which is figured 

 heloM- it. Both came from the rhilii)pine islands, the Xo. 278 

 from Tarlac under the name of Tugui, and Xo. 280 from the island 

 of Palawan under the mime of Invod. In 1)oth races there are 

 formidable spinv roots and in both the flavour of the tuljers is 

 slightly bitter. 



The lowest block on plate 9, represents the most distinct of 

 all the races, a plant which produces the biggest tubers of all aud 

 bears them very diffusely: moreover it is the race which freely 

 produces male flowers. 



It occurs in the Phili].>pine islands, whence it has been oljtained 

 and grown from four localities, e.g. 

 Xo. 272 Luzon, but the exact locality unrecorded. 

 Xo. 282 from cultivation in the Province of Katangas, where it is 



called Tugui 

 Xo. 270 from cultivation in the Province of Pangasinan, where it 



is called Carat 

 Xo. 2S4 from the Mountain Province, where it occurs wild, and is 

 called Buga. 



The large characteristic tubers tune attained in the Singapore 

 plots the weight of 5 lbs. (i (»/. (24:!S grammes), and the longest 

 stalk of anv one measured was just over a metre in length. The 

 tubers are denselv covered with short rootlets. At the base of the 

 stem nun- be found verv f(n-niidablv armed spiny roots but they in 

 no wav cover the diffuse tubers which lie far beyond their jn'o- 

 tection. And what is interesting about these tubers is that they 

 may be formed quite close to the surfa<-e of the soil as if inviting 

 the attack of pigs. 



