GEOGRAPHICAL STATISTICS OF THE EUROPEAN FLORA. 185 
Species, Avge. Species. Avge 
Ranuneulacee. . 180 3°52 | Campanulaceer . 133 1-82 
i 38 ‘66 | Scrophulariacer . 265 2°32 
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Crucifere . . . 
Caryophyllacee . 350 2°32 
Leguminose . . 644 2°39 | Boraginacee . . 150 2°32 
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Sie “pease! 26 3°36 | Liliacew . . . 185 2:12 
Umbellifere . . 368 2°44 | Cyperacee. . , 114 4 65 
Rubi " Graminacew . . 358 3°10 
Taken together they average 2°50 against 2:99, the average of the 
remainder of the flora. Classing the Orders, according to the number 
of species they comprise all over the world, into ‘‘ large” with over 
1000 species, ‘‘ moderate” with 500 to 1000, and ‘‘ small” with 
fewer than 500, we get the following averages :— 
Speci Average. 
4222 bea to ™ oe “ large” Orders - ope 
Til? * moderate” Orden: Oo 
1249 ‘“ " * email” Orders . ‘ » SST 
Like the British averages a ld ascertained, they are in inverse 
proportion to the size of the Order 
(To be ret 
A sew Orper or Alex. 
On the Bie gcse and sapeeete Arrangement of the i st en 
er of Alga. By Vuir Brecurr Upsala. 
1877. 
One of the principal characters of this Order, represented by the pei 
genus Pithophora, is a branched thallus, the branches taking origin 
— the upper part of the mother-cell at a short se a a ” 
n examining an individual, one sees that it consists of t 
es , a unicellular usually ineegpen e basal pore (the i rhizoid > 
part), and a multicellular usually bran hed ‘‘cauloid” part. Ramifi- 
Ss. 
in five open. species (P. Kewens orp. 
Zeller’) either of the first or second degree (and sometimes opposite in 
the last two); while in P. Roettleri a third degree of ramification is 
met with, the branches of the first degree being placed three (some- 
times four) i in a whorl, but those of the second and third either singly 
or in pairs. he cells which bear these branches are either ordinary 
or spores, rarely ‘‘ subsporal ” cells (to be spoken of presently). The 
lateral reaches which are most usually single, have . Reese to 
not from a point near the top, but from some 
— Lan Se, sa the base, of the mother-cell. The rhizoid part 
consists, as has already been mentioned, in most cases of a snes? ne un- 
branched cell, though sometimes several-celled rhizoid 
ido in two of the species ol can occasionally pe law 
the other hand, the ciel ep part is sometimes not even composed of 
