February 23, 1905] 



NA TURE 



397 



The final stage of the pearl oyster cestode was sup- 

 posed to be undergone within the body of an elasmo- 

 branch which fed upon BaUstes. But, so far, the only 

 elasmobranch tetrarhynchid which the authors have 

 examined was obtained from the spiral valve of a sting 

 ray (Taeniura mclanospilos), and this larva was of a 

 species quite distinct from either the Balistes or oyster 

 larvae. It is to be noted, however, that from this ray 

 two perfect specimens of Balistes were taken. 



Thus, though we may yet find that the sequence of 

 hosts is as was indicated in the first volume of this 

 report, we are at present left somewhat in doubt. In 

 due time, doubtless, IVIessrs. Shipley and Hornell, the 

 authors of this really fascinating section, will solve 

 the riddle. 



We have de'alt at some length on this matter be- 

 cause, apart from its interest as a sequence of stirring 

 events in the life-history of a very humble organism, 

 it has considerable importance from an economic 

 point of view : since, when the chain of evidence is 

 complete, it may be possible, as was first suggested 

 by Keelart in 1857, to raise the percentage of pearls 

 by infecting oysters in other beds with their parasites. 



Prof. Jeffrey Bell contributes some notes on the 

 echinoderms, appended to a description of the species 

 collected, by Prof. Herdman. Although these notes 

 barely fill three pages, Prof. Bell has crowded into this 

 space some trenchant criticisms and some really 

 valuable facts. 



The reports on the arthropods are full of interesting 

 matter, and deal with a large number of new species ; 

 but we venture to think that a longer summary of the 

 principal results arrived at would have added to the 

 usefulness of these chapters. Dr. Caiman's work on 

 the Cumacea will be welcomed, inasmuch as no species 

 of this group have hitherto been described from any 

 part of the Indian Ocean. 



The collection of cephalopods has been worked out 

 by Dr. VV. E. Hoyle. Though small, it contained one 

 new species of unusual interest. This was a small 

 octopus, which has been named Polypus arborescens 

 on account of the presence of curious branched pro- 

 cesses scattered all over the body, some of which are 

 surmounted by a tuft of fibrils. .After a most careful 

 study Dr. Hoyle is still uncertain as to their purpose. 

 He dwells at considerable length upon their micro- 

 scopical structure. He is satisfied that they are not 

 parasitic organisms, nor are they, he considers, 

 glandular or phosphorescent organs. The fact that no 

 nerves have been traced to them would seem to show 

 that they are not tactile bodies, yet on the whole he 

 considers that it is this function which they perform. 

 Prof. Herdman, who has studied the living animal in 

 a small tank, describes these mysterious processes as 

 being contractile, and " kept frequently moving — un- 

 coiling to a considerable length and then curling up 

 again suddenly." This seems to suggest that they 

 may be alluring organs comparable to the waving flag 

 of the angler-fish or the long, worm-like tongue of 

 the " mata-mata " tortoise. 

 The fishes collected during this investigation have 

 been described by Mr. J. Johnstone. Twelve species 

 in all are dealt with. 



The most interesting feature of this report is that 

 concerning the supposed naso-pharyngeal passage in 

 Cynoglossus. Kyle, in igoo, described in this genus 

 a curious nasal sac, which, he believed, communicated 

 with the mouth by means of a pore in the floor of the 

 sac, a feature which he regarded as of considerable 

 morphological importance. 



Mr. Johnstone examined several species belonging to 

 this genus, and in no case did he find this naso- 

 pharyngeal passage. But what is really interesting 

 is the fact that he found this cavitv, on more than one 

 occasion, inhabited bv a copepod. Since this creature 



NO. 1843, "^o^- 7^] 



anchors itself by hooks, the presence of an occasional 

 hole in the floor of this chamber is not to be wondered 

 at! 



There is a wealth of plates in this volume, all of 

 which are as good of their kind as one could wish. 

 The same cannot be said of one or two of the text 

 figures, however, which leave much to be desired — ' 

 notably the figure of the dissection of a pearl oyster 

 on p. 43. 



Yet another volume is required to complete this re- 

 port ; this is promised early next year. Judging by 

 the standard set by the two volumes now issued, the 

 complete work will form one of the most valuable 

 commentaries on a great industry yet issued. 



W. P. P. 



NOTES. 



At the invitation of the British Association, the local 

 committee in Johannesburg has nominated the following 

 as vice-presidents and secretaries respectively of the different 

 sections for the meeting in South Africa, the general 

 arrangements of which were described in N.«ure of 

 February 2 (p. 323) : — MathemaUcs and Physical Science — 

 vice-president. Dr. Breyer ; secretary, Mr. R. T. A. Innes. 

 Chemistry— Ut. J. R. Williams, Mr. W. A. Caldecott. 

 Geology — Dr. Corstorphine, Dr. Molengraaff. Zoology — 

 Dr. Gunning, Dr. Fakes. Geography. Mr. E. H. V. Mel- 

 vill, Mr. F. Flowers. Economic Science and Statistics — 

 Mr. S. Evans, Mr. Robert A. Ababrelton. Engineering- 

 Mr. S. Jennings, Mr. E. Williams. Anthropology— Dr. 

 Schonland, Mr. A. von Dessauer. Physiology—SW Kendal 

 Franks, Dr. A. Mackenzie. Botany — Mr. Burtt Davy, 

 Prof. Pearson. Educational Science — Mr. E. B. Sargant, 

 Prof. Hele-Shaw. 



The Hunterian oration delivered by Mr. John Tweedy 

 at the Royal College of Surgeons on February 14, and 

 abridged elsewhere in this issue, contains several interest- 

 ing references to the growth of natural knowledge by the 

 use of the experimental method, with illustrations from 

 John Hunter's work. It has been said that though Hunter 

 had never read Bacon, his method was as strictly Baconian 

 as if he had. Mr. Tweedy pointed out that this view is 

 based upon a complete misinterpretation of the Baconian 

 system. Francis Bacon himself neither knew nor under- 

 stood the physical sciences, and his spirit was much less 

 modern than that of his illustrious namesake, Roger 

 Bacon, who lived three hundred years before him. John 

 Hunter did not follow the mechanical methods of the 

 Baconian system, but he possessed every moral and intel- 

 lectual qualification for useful scientific research— a fertile 

 imagination ready to suggest possible relations of facts, 

 openness ot mind, and a conscientious scientific spirit that 

 submitted every hypothesis to the test of observation and 

 experiment, taking nothing on trust. Mr. Tweedy occu- 

 pied the chair at the festival dinner held at the college in 

 the evening of February 14, when there were present, 

 among others :— Prof. C. AUbutt, Sir W. Broadbent, Sir 

 Lauder Brunton, Sir D. Duckworth, Sir Harry Johnston, 

 Sir Norman Lockyer, Sir W. Ramsay, Prof. C. Stewart, 

 Sir W. T. Thiselton-Dyer, Prof. W. A. Tilden, and 

 Sir F. Treves. 



The death on February 9, at the age of forty-four, of 

 Mr. F. O. Pickard-Cambridge makes a break it will be 

 impossible to fill in the ranks of British arachnologists. 

 From boyhood he had devoted himself to the study of 

 English spiders, and was rightly regarded as the leading 

 authority upon this subject. He completed, moreover, in 

 1904, his monograph of the Central .American spiders for 



