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ON AGARICUS ASCOPHORUS. Peck. 



By MoNs, J. DE Seynes. 



(Flate 46.; 



In 1872 Mr. C. H. Peck described, in the Twenty- Fourth Report 

 of State Museum of Natural History for New York, a new species 

 of Agaricus under the name of Ag. (Hebeloma) ascopJiorus, of 

 which he says " spores produced, in globose asci, borne on a thick 

 tapering, penetrating peduncle, twelve or more spores in ascus." 

 I had the advantage of examining a specimen of this Agaricus 

 sent by M. Cooke ; it showed all the outward characters of sincere 

 Agaric, though it ought to be classed among the Ascomycetes, if 

 it showed asci on the hymenium. This is the real structure of 

 this hymenium; the basidia have the same appearance as in most 

 Agarics, sterigmata are seen on the dried specimen. It is difficult 

 to find spores still borne on basidia; I have, nevertheless, seen a 

 young spore borne on a basidium by the sterigma. The loose spores 

 are oval, ferrugineous, and the youngest sometimes bear a fragment 

 of sterigmata ; they are in length "0,006 m.m. or "0,007 m.m., and in 

 width -0,004 m.m. 



I have not discovered other &pores, but the hymenium shows 

 numerous Cystidia, more or less deformed by dessication, and con- 

 taining a thick yellow and condensed protoplasma. Warm water is 

 not sufficient to give back to the Cystidia their former shape, but 

 after they have been boiled in a solution of potash they can be 

 seen returning to a regular shape. They nearly all have the form 

 of a bottle ; the lower part swelled, oval, attenuated at the bottom, 

 and surmounted by a neck attenuated at its end. This neck is 

 itself slightly swelled in the middle. I suppose these Cystidia 

 to exude the protoplasma they contain, as 1 have noticed it to be 

 the case on the Ag. rimosus, rutilus, etc. It is a mass of substance 

 exuded from the extremity of the Cystidium, that must have been 

 taken for an ascus borne on a penetrating peduncle. 



I have met with some disposed in the same manner in the Ag. 

 riviosus. ]t is no wonder that spores are found glued in the inside 

 of that secretion, and that they easily cause illusion ; but what 

 makes us hesitate is the number of spores indicated — 12 or 

 more. Such a large number of spores contained in the secretion 

 of a Cystidium would produce a mass superior to the dimension of the 

 Cystidium itself, and it is very possible that vacuoles, or fat nucleoles 

 gathered in the seci'eted substance, have been the reason of that 

 illusion. It would be easy to explain if we could suppose from the 

 description that it is the Cystidia itself the author has taken for 

 an ascus ; but the indication of an ascus borne by a tapering peduncle 

 penetrating can only be explained by a secretion borne by the taper- 

 ing extremity of a Cystidium. I have never found any Cystidium 

 in that state on the specimen I have studied, but I have often met 



