153 
solstitialis, L. (fig. 62) and Helminthia echioides, Gertn. (fig. 63). The former is black, 
tapered towards the base, and usually without the pappus; the latter never has the pappus, 
is yellowish brown or orange, transversely striated, and either straight or bent. 
NZIS 
Ws \\ fem \ 
SUE VA 
M SY = RAN ¢ I — 
SEM SERS Za 
SR : Ae) — 
SEX - Wes Z. nas, * 
SSSR 
(Hes So yy —— 
ae 
See eo yy ~s 
SNA ie a 
SN, = 
5. 
} 7 
| 
\' 
Se 
Wy A AN 
FAT IP pees 
awiaicas 
( 
ae 
p 
o b 
Fig. 63. (After Nobbe.) Fig. 64. 
Helminthia. _ Trefoil. — 
Helminthia echioides, Gertn. Medicago lupulina, L. 
a. Fruit of a dise floret natural size. b. Fruit of a ray a. The pod seated in the calyx, 
floret with the pappus < 7. c. The same asa X 7. x 7. 
d. The same as 6. but without the pappus < 7. e. Fruit b, The seed, natural size. 
with pappus, natural size. c. The seed, < 7. 
Adulteration is rarely attempted. Trefoil (Medicago lupulina L.) is often found Adulterations. 
mixed with lucerne; the seed (fig. 64) is smaller, roundish ovate, greenish-yellow and 
shining; it is at once recognised by the projecting tip of the radicle. Lucerne seed is 
more reniform, larger, somewhat angular from the mutual pressure of the seeds in the 
pod, flatter, and coloured yellow like the yolk of an egg. Seed from southern France is 
not shining and the yellow is of a deeper tint. Attempts at adulteration with seeds of 
Melilotus are rare and at once detected by the odour of coumarine and the dull colour; they are 
not reniform and the radicle is very distinctly marked off from the cotyledons. Melilot 
pods are sometimes present. Seeds of Medicago maculata and Medicago denticulata which 
come from South America are sometimes used as adulterants. The pods from which these 
seeds are obtained are covered with hook-like or scissor-like bristles which become entangled 
in the wool of sheep (figs. 66 and 67). Wool containing these pods is imported into Europe; 
ultimately, the seeds are obtained as a by-product of the wool. Closely resembling as 
they do the seeds of lucerne, they are either mixed with genuine lucerne or sold separately 
as lucerne, Chili lucerne, Buenos-Ayres lucerne, etc. The plants grown from such seed 
are annual with stems lying on the ground and of no agricultural value whatever. ‘The 
seeds are larger, quite dull, and distinctly kidney-shaped; by these characters, they may 
be distinguished from genuine seed. The seeds of MZ. maculata are readily known by the 
projecting, often red tinted apex of the radicle. Small bent steel rods (fig. 70) — the 
fragments of the carding-combs used in preparing the wool — are also distinctive. 
20 
- 
- 
=. 
a 
5 
= 
