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however a significant representative in the Spheriacei, in Fungi, give 
marked distinction to our next sub-family (7rypetheliei) notwithstanding 
its often difficult relations to Pyrenula ; and Trypethelium has been 
universally accepted as an analogue of Pertusaria. And the final, varied 
deformation of the lecanorine type (Urceolarie?, finding its centre in 
Thelotrema) is fitly represented here by our last sub-family — the Pyrenulei. 
Estimates of the limitation of species vary so much in this tribe, that 
while one European author reckons not far from two hundred specific 
forms in Germany alone, another scarcely allows two hundred and fifty 
to be known to science. The tribe is remarkable for the very small pro- 
portion of types referable to the colourless spore-series. 
Fam. I.—ENDOCARPHEI, Th. Fr. 
Thallus foliaceus 1. squameeformis. 
As in immersed types of Thelotrema, it is the interior exciple (amphi- 
thecium) which plays the largest part in the family before us, almost 
indeed constituting the fructification in its principal group; and the 
perithecium, which alone is equivalent to the at length marginant hypo- 
thecium of the higher tribes, is proportionally diminished. Extreme then 
as is the position of Endocarpon, as exhibited in its best-developed forms 
(comparable only with Umbilicaria) it is not to these, but far humbler 
representatives of the generic type, and indeed to the analogies afforded 
by the next family that we are to look for the full explication of its fruit- 
character. 
And this remark may possibly prove as applicable to the difficulties of 
the spores, as to those of the excipular envelopes. The now largely 
accepted separation of Dermatocarpon, Eschw., from Hndocarpon, rests 
on not dissimilar grounds to those which are as generally taken to distin- 
guish Pannaria from Lecothecium, Trev.; the differences in the thallus 
being corroborated, in both cases, by modifications of the spore. In the 
latter however this modification is only a gradal difference of the same 
spore-type, assuming here the same direction of ascent which so often 
accompanies the degradation of the thallus. Two Italian lichens not 
otherwise distinguishable from Dermatocarpon (Placidiopsis, Beitr., 
Koerb.) differ from the foliaceous species in precisely the same way. And 
the only distinction in the case of Endocarpon, Hedw., lies in the fact that 
the spore here is muriform ; requiring us to consider that this last little 
group belongs to a different spore-series, and therefore genus, from 
Dermatocarpon, or else that the latter is to be taken as offering a decol- 
orate exhibition of a stage in the differentiation of the same, coloured 
spore. The last view has already commended itself in Umbilicaria, and 
finds present support in the great predominance of the coloured spore- 
series in the Verrucariacei. The commonly decolorate exhibition of this 
