57 



sures has hitherto been pubUshed of any weU-defined fungus belonging to the 

 Pala'ozoic series of rocks. It is, however, possible that a paper in the Ann^ds 

 and Magazine of Natural History, 4th series, vol. iv., 1869, p. 221, and tabb. ix. 

 and X., describes and illustrates a fungus of a somewhat similar nature mth my 

 Peronosperites. The paper in question is communicated by Messrs. Albany 

 Hancock F L S., and Thomas Atthey, and pui-ports to describe five species of 

 ' Irchaglricon' from the Cramlington black shale. The authors state that the 

 fossU fungus has been found at Newsham and in other localities. They how- 

 ever describe 'lenticular swellings' with a 'reticulated surface,' which I have 

 never seen, and spore-like bodies vvithin the myceUum, which is clearly an error of 

 observation. The authors also refer their plants to SclcroUum stipUatum, and 

 they say they can find ' no important difierence ' to distinguish this latter plant 

 from their coal fungi. Of course, Sclerotiuvi is not a fungus at aU, but a mass of 

 condensed mycelium, and the Cramlington plants do not resemble Sclerotia. 



" One of the most instructive groups of threads and fruits, or more properly 

 speaHng, mycelia and zoosporangia (or oogonia) as seen within the vascular axis 

 of the Lepidodendron, has been enlarged 250 diameters. Beginmng with the 

 myceUum, a close examination of this, shows that it is furnished with numerous 

 joints, or septa. If, therefore, any reUance is to be placed upon the modern dis- 

 tinguishing characters of the now Uving species of the Peronospora and Pythium, 

 as ftimished by a septate or non-septate myceUum, then the fossU parasite belongs 

 to Peronospora, and cannot belong to Pythium or any of the Saprolegnie*. The 

 oogonia do not agree v^-ith those of Cystopus. Within many of the fossd oogonia 

 of the group illustrated, this diflferentiation of the protoplasm into zoospores is 

 clearly seen ; but if any doubt could exist as to the exact nature of the diflferentia- 

 tion, then other oogonia (or zoosporangia) on the same sUde, show the contamed 

 zoospores mth a clearness not to be exceeded by any Uving specimen of the 

 present time. One of the most perfect groups of these Pateozoic bladders, con- 

 taining the once mobile spores, has been enlarged to 400 diameters, and the 

 wonderful fact becomes manifest, that the bladder is exactly the same m size and 

 character with average oogonia of the present day, especiaUy with the same organ- 

 isms belonging to Peronospora infcstans. The contained zoospores are, moreover, 

 the same in form and dimensions %vith the zoospores of Peronospora infcstans, when 

 measured to the ten thousandth part of an inch. For comparison, an oogomum and 

 group of free zoospores have been enlarged 400 diameters, and belonging to the 

 fungus of the potato disease. On examination it will be seen that the orgamsms 

 are apparently identical. The average number of zoospores m each oogomum is 

 alBO the same, viz., seven or eight. The aerial condition of the fungus has not yet 

 been observed. 



"In Peronosporites antiquarius, we then, probably, have one of the simple 

 primordial plants of the great family of fungi. The Peronospora. are closely alUed 

 to the Algse-so closely, indeed, that De Bary says the species of the former may, 

 with reason, be compared mth the species of one group of the latter, named Sapro- 



