HARDWICKE'S SCIENCE-GOSSIP. 



63 



course, do not represent the external appearance of 

 the plant when growing, as the real epidermal layer 

 was outside of the fibrous zone. 



The many varieties of these sandstone casts indicate 

 that there were probably many species of Lyginoden- 

 drons. 



They are found in the sandstone rocks in the mill- 

 stone grit series, and at various horizons in the coal 

 strata. They have also a great horizontal range, 

 occurring, as has been shown, in the Scotch coalfield 

 whence the late Mr. Gourlie obtained his specimens, 

 and also in Lancashire and Yorkshire, and very 

 probably in other coalfields. The great range oi 

 these plants and the abundance and large size of their 

 remains, prove that they attained to arborescent di- 

 mensions and flourished in great numbers, and that 

 they formed a very important part of the flora of the 

 Carboniferous age. 



The question maybe asked, What are these plants : 

 but, like many other questions, it is far more easily 

 asked than answered. I have already pointed out 

 that Lyginodendron Ohihanmttn possesses affinities 

 with both the Lycopodiaceas and the ferns of the 

 same geological age, and that it was originally 

 described as a Dadoxylon or fossil pine. But the 

 fact is, the stem of Lyginodendron is so very 

 anomalous in its structure, that we shall have to learn 

 a great deal more about the plant before we can 

 place it in its proper botanical position. 



We are not sufficiently acquainted with its mode 

 of branching, or whether the branches partook of the 

 nature and form of fern-like fronds as has been 

 suggested, or otherwise, and nothing whatever is 

 known about its roots; while in regard to the most 

 important point as to the character of its reproductive 

 organs, we have yet to learn whether it bore seeds or 

 spores. It is, therefore, very obvious that, until we 

 know more about these parts, especially about the 

 character of its fructification, such an anomalous 

 structure as is presented to us in the stem of Lygino- 

 dendron must yield us an uncertain guide to its proper 

 classification. 



This plant has been supposed by some fossil 

 botanists to have been the parent of some of the 

 gymnospermous seeds which occur so plentifully in 

 the coal measures, and the great difference which 

 exists between its structure and that of the true 

 fossil pine. Dadoxylon has been accounted for in the 

 very great difference in the habitats of the two plants. 

 It has also been suggested that the seeds may have 

 been brought from a distance by water and deposited 

 among the debris of other plants. In the case of the 

 seeds found in sandstone rocks and in limestone shales 

 such was undoubtedly often the case, but my experience 

 of the manner in which these seeds occur in the coal 

 strata, and especially those which are found in our 

 coal balls, leads me to think that it is highly improb- 

 able that they have been brought from any great 

 distance. On the contrary, there is an abundance of 



evidence to prove that the parent-trees must have 

 flourished on the spot where the seeds are now found. 

 In our coal balls, numerous species of Trigono- 

 carpons and other gymnospermous seeds have been 

 found associated with [the remains of the ordinary 

 coal plants, such as stems, leaves, fruits, and abun- 

 dance of spores. The occurrence of spores along with 

 the larger fragments is almost certain proof that such 

 vegetable debris must have been deposited on land 

 and became entombed on the spot ; for if water had 

 carried them away from the place where they had 

 been originally deposited, the spores being so light 

 could not have been deposited along with the heavier 

 seeds and other fragments. 



Nor do I believe that the parents of the seeds 

 could have been at all rare, or more easily destroyed 

 than many of the other coal plants ; hence I am 

 forced to the conclusion that we must look to some 

 of the fossil plants with which we are already familiar 

 for the parentage of these seeds. Whether Lygino- 

 dendron may prove to be one of these we must leave 

 for future discoveries to tell us, but from its near 

 affinity to Dadoxylon it is not improbable that such 

 may have been the case. 



POND LIFE IN MIDWINTER. 



IN several numbers of Science-Gossip last year, 

 we were reminded of the fallacy of the opinion 

 that ponds are destitute of life during the winter 

 months ; and I should like to add my testimony to 

 that borne by the Rev. W. C. Hey, M.A., and others, 

 on this subject. More than once, after reading of 

 some rare or common inhabitant of our ponds, I have 

 had my desire to search for it dashed to the ground 

 by being informed that it was not to be found during 

 the winter months ! Last December, when I told a 

 naturalist that I had found plenty of the very common 

 cyclops and daphnia in some pump water, he told 

 me they had no business there at that time of 

 year ! But in the month of January last, I deter- 

 mined to put aside and ignore all that had pre- 

 viously obtained credence with respect to pond life 

 in winter, and search for myself, in order to see if 

 things were as they had been represented. With the 

 memory fresh on my mind of what I caught in two 

 excursions, I can truly say I am thankful I did so. 

 I made my first excursion on Jan. 8, to a pond about 

 two miles from Southampton, and I was soon con- 

 vinced that this particular pond at any rate was not 

 devoid of life, even though I visited it on one of the 

 coldest days we had during the winter, and with a 

 keen north-east wind blowing all the time. On this 

 first visit, the only "fishing" apparatus I had with 

 me was a bottlejwifh a narrow neck, attached to some 

 odd pieces of string I happened to have in my pocket. 

 Notwithstanding all disadvantages, before I left the 

 pond I had managed to secure a good number of the 



