y; net well
differentiated, the threads delicate, transparent, yellow, connecting
large black nodules, running from one to the other in pairs or sometimes
three together, free ends not numerous, the meshes few-sided, often
triangular; spores in mass, dull olivaceous, under the lens pallid,
nearly smooth, 6-7 mu.

A very rare species, if indeed it occur in this country. At least the
form figured by Rostafinski, Tab. II., Fig. 27, and Massee, Pl. 1, Fig.
11, has not come to our notice. The parallelism of the net threads is a
touch added by Rostafinski; Schrader does not mention it. Lister makes
this species include the preceding. The form described in _Bull. Lab.
Nat. Hist. Ia._ II., p. 119, is _C. dictydioides_.

Reported from New York, New England and Pennsylvania.

In the English _Monograph_ we are repeatedly assured that this species
is common in the United States. The statement is made possible only by
the inclusion of the form originally described from America and truly
abundant east of the Rocky Mountains, _C. dictydioides_ Cke. & Balf.;
_C. intricata_, by all accounts, just as preeminently the species of
Europe. It is true that Schrader did not emphasize the parallel
connecting threads by which later authorities distinguish the form; he
had little occasion so to do, even did his figures intend accuracy in
each detail, which they did not, and Rostafinski's, though his drawing
is a diagram, certainly knew what he was doing. Cooke, in his list for
Great Britain, quotes the Polish text without dissent, and Massee
follows and illustrates; so that there can be no doubt as to what the
European species is.

In any cribraria the presence or relative obsolesence, of the calyculus
is of little taxonomic import since that structure is variable in every
species. In the latest edition of Mr. Lister's work, the American form
is entered as a variety in "hot-houses"; apparently adventitious; it is
indeed related to the European form but is a geographic species.

9. CRIBRARIA PIRIFORMIS _Schrader._

PLATE XVII., Fig. 9; PLATE XIX., Fig. 9.

1797. _Cribraria piriformis_ Schrad., _Nov. Gen. Pl._, p. 4.

Sporangia gregarious, small, .3-.5 mm., turbinate or globose, erect,
purplish brown, stipitate; stipe comparatively short, tapering upward,
longitudinally furrowed, purple or brown; calyculus very well defined,
about one-third the sporangium, not ribbed, flattened or even umbilicate
below, the margin plainly denticulate,