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James Small. 
itulum just before anthesis. The calyculus in that group is frequently 
soft, herbaceous and easily removed without disturbing the rest of 
the capitulurn. The narrow, elongated structures on the outside 
of the fossil are too flat and undulate to be achenes : on the other 
hand they cannot he florets because they are attached directly 
to the receptacle without the least vestige of an ovary. The writer 
suggests, therefore, that this fossil is a capitulurn with only the 
outer bracts or calyculus missing, and that it shows a suh-hiseriate 
involucre similar to that which is the chief part of the fossil 
Hieracites stellatus, hut with the equal involucral bracts which are 
common in the Cichorieae. 
We have then two fossil examples of involucre, H. stellatus 
and H. nudatus, which are both sub-hiseriate. The latter is of a 
Cichoriaceous type but the former, although compared by Saporta 
with that of Inula pulicaria , is very closely similar to the involucre 
of Senecio glaucus figured above (Chap. VII, Fig. 21). Leaving the 
exact affinity as impossible to determine in the meantime, one 
point is clearly proved, namely, that the only involucres known 
in the fossil condition are sub-hiseriate, and one of them shows the 
scar of a distinct calyculus. This is in accordance with the view 
expressed in Chap. VI, B, on the primitiveness of the involucre with 
an uniseriate pericline and a slightly developed calyculus. 
Considering now the evidence which has a bearing on the 
dates of appearance in Europe of the various tribes, we find the 
Cichorieae indicated by a number of beaked achenes, by the 
capitulurn of Hieracites nudatus, and by leaves similar to those of 
recent species of the tribe. These occur in the lower Oligocene, 
so that, if the views expressed in Chap. X on the successive origin 
of the tribes from the Senecioneae are correct, most if not all of 
the tribes had been differentiated at the beginning of the Oligocene 
period. The absence of any fossils from the Aix deposits which 
could be ascribed to the Calenduleae or Arctotideae, although only 
negative evidence, is interesting on account of the suggestion in 
Chap. X, D, of the origin of these tribes at a later date than that 
of the Cichorieae. The decided development of the Cichorieae in 
Oligocene and Miocene times is in accordance with the occurrence 
of a number of the same tribe in the Pliocene and later floras. An 
interesting point in connection with the suggested age of the genus 
Lactuca (Chap. X, C, and Fig. 31) is the similarity of Cypselites 
spoliatus to the fruits of that genus. The Asiatic affinity of two 
species of Crepis from the Middle Pliocene is in accordance with 
the suggested migration of the present Asiatic Cichoriese from the 
Mediterranean region. The absence of any fossil species of 
