434 



NATURE 



[March 8, 1894 



Apogamy in Pteris serrulata (L. fil.) var. cristata. 



Cases of apogamy are so rare and so intrinsically interesting, 

 that it may be worth the while to record at once the following 

 fact :— 



About a fortnight ago, while preparing prothallia for im- 

 bedding in paraffin, my attention was called by a student to a 

 specimen obtained from a pot containing a fine plant of Pleris 

 serritlata ci'isiaia. 



The prothallium was of somewhat unusual form, perfectly 

 destitute of archegonia and antheridia, but yet had midway 

 between base and apex a peculiar protuberance. This I 

 suspected to be a young sporophyte apogamously developed. 



The prothallium was imbedded in the usual way, and yester- 

 day it was cut into a series of sections. These demonstrate 

 conclusively, I think, that the prothallium was apogamous, for 

 while there is no trace of an archegonium, I find, in the first 

 place, a row ofscaia7'iform tracheides, and in the second place — 

 except over a limited area, where I believe the apex of the root 

 has been separated off by the appearance of a conical split — 

 there is no sharp distinction betiueen the cells of the sporophyte 

 and gamciophyte. 



It should be added that my examination of the sections was 

 necessarily a hurried one, and that at present it is impossible to 

 be certain that the prothallium was developed from a spore of 

 P. serrulata cristata. The ferns of the garden and house where 

 the prothallium grew, however, included no known apogamous 

 forms. 



It is not unlikely that I may be unable to follow the matter 

 further, and this must be my excuse for making public, without 

 further investigation, this interesting fact. A. H, Trow. 



University College of South Wales and 

 Monmouthshire, February 27. 



Fireballs. 



The large meteor of February 21 last, mentioned in Nature 

 of March i (p. 419), was also observed by me at Bristol. The 

 time was noted at 7h. i8m., and the meteor was estimated as 

 bright as Jupiter, but its light was much dimmed by the fog, 

 low on the northern horizon, where it appeared. Its direction 

 of flight was not well determined, the path being short and 

 rapidly traversed in a place barren of visible stars, but it was 

 roughly recorded as from 252" + 53° to 253^° + 49". Com- 

 paring it with the description by Mr. Greig at Dundee, and 

 with notes from North Lincolnshire and other places, it seems 

 the meteor disappeared at a height of about thirty miles over 

 Bolton, Lancashire ; but the place and height of its first appear- 

 ance are not satisfactorily indicated. The probable radiant is in 

 Ursa Major. A good observation from Ireland, or the north- 

 west part of England, would be very useful in assigning the 

 precise path. 



A fine example of a fireball, visible in sunshine, was afiforded 

 by the meteor of February 8, oh. 28m. p.m., which appears to 

 have been very widely observed in this country. Its real path was 

 from a point above the Irish Sea, west of Southport, where its 

 approximate elevation was seventy-five or eighty miles, and from 

 thence it passed rapidly over Lancashire into Yorkshire, finally 

 disappearing near Leeds at a height of twenty miles, or possibly 

 less. Its radiant point was in Hercules, and the direction of its 

 motion from west by south to east by north. This daylight fire- 

 ball may have had its origin in the same system as that which 

 supplied the brilliant fireball seen in the evening twilight of 

 February 7, 1863, the radiant of which was about 270° + 35''. 



Bristol, March 4. W. F. Denning. 



Astronomy in Poetry. 



A propos of the subject of " Astronomy in Poetry," permit me 

 to quote one verse from " The Faerie Queene " of Spenser : — 

 Yet all these were, when no man did them know, 

 Yet have from wisest ages hidden beene : 

 And later times thinges more unknowne shall show. 

 Why then should witiesse man so much misweene, 

 That nothing is but that which he hath scene ? 

 What if within the Moones fayre shining spheare, 

 What if in every other starre unseene 

 Of other worlds he happily should heare. 

 He wonder would much more : yet such to some appeare. 



I have followed the spelling and the punctuation of the text of 

 the "Globe" edition (1879). 



Kendal, Westmorland. G. W. Murdoch. 



NO. I 27 I, VOL. 49] 



RECENT PUBLICA TIONS OF THE AMERICAN- 

 GEOLOGICAL SURVEY. 



nnO initiate and to be left behind — that seems to be 

 -*■ the fate of England in the latter half of the nine- 

 teenth century. In science, at any rate, it is too often 

 so. A sight of the volumes — fourteen in number, the 

 earliest dated in 1891 — with which our table is loaded, a 

 glance at those which are already ranged upon our shelves, 

 indicate that this is emphatically true of the work of the 

 Geological Survey. We mean no reproach to British 

 men of science or to the British surveyors. The State 

 despises the one and starves the other ; and the " people 

 love to have it so " ; for what care they for learning or 

 research, unless it will obviously put money into the 

 pocket ? But this is a large question, and our space will 

 not suffice even for an adequate notice of the volumes 

 before us. These consist of one bound octavo volume 

 on the mineral resources of the United States (the eighth 

 of a series), nine paper-covered numbers of the BuHetifi, 

 slightly larger in size, ranging from thirty to five hundred 

 and fifty pages ; two volumes, still larger, of the Annual 

 Report (eleventh), and yet two volumes of Monographs 

 of quarto size. 



Passing by the first as of commercial rather than of 

 scientific interest, we come to the Bulletin. Four of 

 the numbers, smaller than the others, though they make 

 up to full 220 pages, have little in common. No. 90 is 

 a report of work done in the Division of Chemistry and 

 Physics, mainly during the years 1890-91. It contains 

 several studies and analyses of special minerals, includ- 

 ing a research on certain micas, vermiculites and chlo- 

 rites, and a note on the colloidal sulphides of gold, in 

 which it is suggested that the separation of free gold 

 in the upper strata of the earth's crust may have been 

 effected by the action of sulphuretted hydrogen on chlo- 

 ride of gold, at no very great depth, though at one less 

 than that at which pyrites is formed. The report con- 

 cludes with a number of analyses of miscellaneous rock 

 specimens. No. 91 is a "Record of North American 

 Geology for 1890," a very useful bibliography of papers^ 

 &c., classified not only under names of authors, but also 

 under subjects. No. 93 is a pamphlet by Mr. S. H. 

 Scudder, on " Some insects of special interest, chiefly 

 from Colorado," and No. 94, which is about the same 

 length, is by Mr. E. S. Holden, on " Earthquakes in 

 California in 1890 and 1891." 



The larger volumes of the Bulletin are all " Correla- 

 tion Papers," or memoirs written on some one geological 

 period, by a specially qualified author, "for the pur- 

 pose of summarising existing knowledge with reference 

 to the geologic formations of North America, and espe- 

 cially of the United States ; of discussing the correlation 

 of formations found in different parts of the country with 

 one another and with formations in other countries ; and 

 of discussing the principles of geological correlation in 

 the light of American phenomena." Of these four 

 memoirs the largest (No. 86), written by Prof. C. R. 

 van Hise, deals with the "Archaean and Algonkian " 

 systems. 



By these names the author designates the vast mass of 

 rocks which lies beneath the OlencUus zone of the Cam- 

 brian system. In dealing with the subject he has adopted 

 the following method :— Each chapter treats of some 

 important district. It gives full abstracts of the more 

 important papers bearing on the geology of that district, 

 which is followed by a bibliographical list, and concluded 

 by a summary of the results. More than four hundred 

 pages are thus occupied, and the work is ended by along 

 chapter (about eighty pages) on "general successions 

 and discussion of principles." 



The author employs the term Algonkian for "the 

 pre-Olenellus elastics and their equivalent crystallines," 

 and Archaean for the completely crystalline rocks below 



