492 



NATURE 



[Sept. 14, 1882 



on changes in mollusca into harmony with the more striking 

 changes indicated by the plants. A grouping is suggested which 

 separates the London Clay from the Lower Eocene, and brackets. 

 it with the Lower Bagshot Beds as a Middle Eocene. The 

 Middle Bagshot series forms the Upper Eocene, while the Upper 

 Bagshot may remain a member of the same formation, or find a 

 place in the Lower Oligocene. Refers to the changes of climate 

 in the Tertiary epoch. 



On the Classification of the Oligocene Strala in the Hampshire 

 Basin, by J. W. Elwes, describes results of investigations in 

 Hampshire and the Isle of Wight. In the latter district he con- 

 siders that Prof. Edward Forbes was correct in stating that there 

 is only one marine series in the Headon and Brockenhurst group, 

 but he considers, with Prof. Judd, that there are at least two 

 marinezones, the Brockenhurst zone, lying at the base of the series, 

 instead of above the Middle Headon Venus bed. The author 

 found the southerly dip at Totland Bay, as described by Prof. 

 Judd, bnt found no evidence of the local flexure described by 

 that author, by which the latter explains this section, in opposi- 

 tion to the view of the late Edward Forbes. 



On the Outcrop of the Brockenhurst Beds near I.vndhurst, by 

 E. Tawney, M. A. —Fossils characteristic of the rich beds which 

 he had been lately working in the railway cutting near Brocken- 

 hurst, were found by Mr. H. Keeping, at Cut Walk Hill, Lynd- 

 hurst, in 1858. The well at Emery Down, closely adjacent 

 also, yielded the same fossils in 1863. The excavations which 

 the author had lately carried out with the assistance of the Rev. 

 J. Compton, of Minstead, on several sides of this hill, show the 

 succession of the beds to be on the base of the hill. Upper 

 Bagshot sands, next in ascending order, freshwater Lower 

 Heaton, Marine Brockenhurst bed, Valuta geminata zone, fol- 

 lowed by beds not explored, concluding with the freshwater 

 Osborne marls on the top of the bill. The succession is therefore 

 that of Whitecliff Bay. The thickness of beds between the 

 freshwater Lower Heaton and the Osborne marls is about 100 

 feet. The discovery of freshwater Upper Heaton beds at 

 Roydon brick-yard was announced. 



SECTION D— Biology 

 Department of Zoology and Botany 



On a New Principle affecting the Systematic Distribution of the 

 Family of the Torpedinida J and on the Probable Occurrence of 

 the T. Occidental {Storer) on the British Coast, by Prof. Du 

 Bois Reymond, F.R.S.— The author referred to the researches 

 of Prof. Babuchin, of Moscow, on the development of the elec- 

 trical organs of Torpedo, who has established that these organs 

 are formed by the metamorphosis of striated muscle, and that as 

 they grow they increase in size, not by the addition of new 

 columns and septa, but by the growth of the columns and septa, 

 so that the number is the same in adult and young specimens. 

 Pie then passed on to the consideration of the part which this 

 fact — known as " delle Chian's and Babuchin's Law — plays in 

 the distribution of the Torpedinidae. He thought that the 

 average number of columns ought henceforward to form a part 

 of the diagnosis of the species of Torpedinidre — a matter which 

 has hitherto been entirely overlooked by zoologists. He referred 

 to the species of Torpedo of John Hunter, and showed how- 

 Hunter's conclusion that the columns increase in number as well 

 as size was erroneous, and described fully the T. occidentalis on 

 the British coasts. 



On Ccphatisais, a New Form allied to RhabJoplcura [AUman), 

 by Prof. Mcintosh, F.R.S.— This new form was very fully 

 described, and its relation to Khabdopleura of Allman, which we 

 know as a somewhat abnormal Tolyzobn, was discussed. It 

 differs from Rhabdoplcura in regard to the camscium, in the 

 much greater size of the buccal shield, in the remarkable 

 branchial or textacular plumes, in the structure of the pedicle, 

 and the perfectly free condition of the polypides. Cephali-cus 

 and Rhabdopleura agree in the absence of the calyciform mem- 

 branes connecting the bases of the tentacles, in the position of 

 the mouth, which opens behind the buccal shield, in the general 

 structure of the alimentary canal, and in the position of the anus. 

 The development of the young buds is similar. Both forms 

 connect the ordinary Polyzoa with Phoronis. 



On an Instructional System of Arrangement in Provincial 

 Museums, by F. T. Mott. — The author suggests a combination 

 of a typical collection of the entire fauna of the globe with that 

 of the local species, the latter being on the ground row, both 



labels corre- 



scientific and vernacular names being given 

 sponding with a cheap popular guide-book. 



Injurious Parasites of Egypt, by Dr. Cobbold, F. R.S.— 

 Egypt is a grand field for the helminthologist, since not only is 

 that country the headquarters, so to say, of one of the most 

 dangerous of human parasites, but it swarms with others possess- 

 ing scarcely less practical importance, whilst it likewise enjoys 

 the distinction of having made us acquainted with parasitic 

 rarities not known to occur in any other part of the world. 



The most dangerous parasite is Bilharzia \kamatobia. This 

 was so named by me in honour of Dr. Bilharz, who first dis- 

 covered it at Cairo in 1851. A few years later I detected the 

 same species of parasite in a monkey ; and since the year 1856 

 confirmatory discoveries and observations, made both at home 

 and abroad, have very greatly extended, though they have by no 

 means completed, our necessary knowdedge of the natural history 

 of the creature. In this connection it is fitting that we should 

 signalise the labours of Dr. Prospero Sonsino, whose residence 

 in Egypt has enabled him to contribute facts of great interest. 

 It is to Sonsino that we owe our knowledge of the fact that 

 cattle and sheep are also liable to be infested by Bilharzia, but 

 the species is not the same as that which invades man and 

 monkeys. 



The Bilharzia is a genuine fluke parasite of the digenetic kind, 

 and therefore requiring a change of hosts. It differs from the 

 ordinary sheep-fluke and its allies in being unisexual. In other 

 words we have male and female Bilharzia; the male being the 

 stouter of the two sexes. This is an unusual circumstance 

 amongst parasites. Again, these Bilharzia: differ in respect of 

 habitat, for, in tead of occupying the liver-ducts and intestinal 

 tract, as most flukes do, they take up their abode within the 

 blood -vessels of the victim. 



Although the parasites are individually small, the slender 

 females being less than an inch in length, the presence of any 

 considerable number of them gives rise to a formidable malady, 

 which, in some cases, proves fatal. The disorder thus occasioned 

 has received various names, but it is sufficient to speak of it as 

 the endemic hematuria of warm climates. Dismissing the purely 

 professional aspect of the affection, and viewing the matter as a 

 question of public health specially affecting European residents 

 in Egypt, I may state that I have recently seen six officers of the 

 Ea tern Telegraphic Company, who contracted the disorder in 

 the neighbourho d of Sue;-, and also another gentleman who 

 obtained the parasite in Natal. In all of these instances the 

 immediate cause of the parasitic invasion was due to their 

 having carelessly drank unfiltered water. In all the Egyptian 

 ca-es this took place during shooting expeditions along the banks 

 of the Cairo-Suez Canal. 



Thus, all the evidence of a practical sort that we have obtained 

 as to the cause of the endemic is in perfect harmony with that 

 which has been derived from scientific inquiry. So far as our 

 investigations have been pushed, i: is clear that in respect of 

 Bilharzia liamatohia, the natural history phenomena do not 

 differ in any very essential particular from those that occur in 

 the case of ordinary flukes. We have a similar mode of 

 nation, the same rapid growth and development attended with 

 metamorphosis, and likewise a change of hosts. 



Practically it is of little moment what water snail or other 

 aquatic organism holds the cercaria of Bilharzia. Infection fol- 

 lows as well from the ingestion of the free-swimming cercaria as 

 from the ingestion of the intermediate hosts. It comes to the 

 same thing in the end. Canal water-drinking in Egypt is the 

 direct cause of the Bilharzia infection, and ol the consequent 

 endemic hrematuria. This being so, simple filtration is in most 

 cases a sufficient protection. To European residents, therefore, 

 the drying up or damming up of the fresh-water canals is not an 

 unmixed evil, because it insures greater freedom from parasitic 

 clangers ; moreover, it induces efforts to remedy the evil. Of 

 course these efforts will correspond in magnitude with the neces- 

 sities of the case. 



Unfortunately, there are other parasites whose entrance into 

 the human body by means of water-drinking is of constant 

 occurrence, and they are often found associated together iiv one 

 and the same per on. The other specially obnoxious endemic 

 worms are Anchvlostoma duodenal* and Filaria sanguinis hominis. 

 Speaking of the collective rile of the three parasites, Dr. Son- 

 sino says that "they concur in the production of a large mor 

 tality of the natives," and the mischief they thus occasion "is 

 not sufficiently appreciated." 



How fatal the Anchylostoma may prove in other countries 



