﻿Remarks on a Supposed Fossil Fungus. 



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frequently curved; the branches are diverging, generally simple, some- 

 times forked: are obtuse, club-shaped and flat. A comparison of the fig- 

 ure given by Lesquereux, with one given by Professor C. V. Riley in his 

 fifth annual report as State Entomologist of Missouri, p. 103, will illus- 

 trate the resemblances between the fossil and the recent burrow. The 

 burrows made by other species are still more like the fossil. 



W hat now are the prospects of an insectivorous larva living under the 

 bark of a Sigillaria? Were there any species living at the time and place 

 where the fossil was found? In looking over a "Catalogue of Palaeozoic 

 Fossil Insects" compiled by Mr. R. D. Lacoe, and published in 1883, I 

 find no less than five species out of a total of seventy-two fossil insects 

 were found in the same locality as the fossil fungus (?), and in beds of the 

 same age. As there is every probability that the habits of insects in past 

 ages conform in many respects to those at the present time, it may be con- 

 sidered that they went through metamorphoses then as they do now : that 

 the eggs hatched into grubs, the grubs fed, and then spun coccoons or 

 formed the pupa cases, and finally emerged as perfect insects. There 

 can be but little doubt that the RJiizomotfJia Sigillarke is the burrow left 

 under the bark by the grub of some one of the species of insects flourish- 

 ing at the time of the deposition of the coal. 



A specimen of wood recently presented to this Society by Geo. W. 

 Keck, has on it several of these burrows in an excellent state of preserva- 

 tion, and a few remarks as to how they are made may be of interest. 

 Prof. Riley in the report referred to says, that both male and female 

 insects bore into the tree just under the bark. A vertical chamber is ex- 

 cavated in which the female deposits her eggs, numbering from twenty to 

 fifty. When the larvae hatch, they bore in a horizontal direction, away 

 from the central burrow, each in a distinct track, feeding on the inner 

 bark. The perfect insect, a beetle, issues from a small hole in the bark, 

 and*the same cycle recurs. They are very destructive insects, and cause 

 the death of whole groves of hickory trees. In Europe the elm is attacked 

 in the same way. Perhaps in the ancient days insects of similar kinds 

 were just as destructive to the forests, and in some cases have left their bur- 

 rows to tell the story. 



