362 SECTIONAL TRANSACTIONS,— D. 



8. Presidential Address by Prof. J. Graham Kerr, F.K.S., on Biology 



and the Training of the Citizen. (See p. 102.) 



9. Dr. R. T. GuNTHER. — A New Sense Organ in Siphonophora. 



The material investigated was sent home by Dr. Gilchrist from the Cape of Good 

 Hope for examination in the Daubeny Laboratory. 



The new organ was observed in a series of swim-bells from the nectosome of 

 Crystallodes vitrea of Haeckel, a member of the Agalmid group of Siphonophora, well 

 known for their perfectly co-ordinated powers of swimming and for their remarkable 

 crystalline forms. In them the cavity of the swim-bells is prolonged into two horns, 

 ensheathed in a special musculature, the apparent purpose of which is to direct the 

 expelled water to one side or to the other, and thus to steer the animal when swimming. 

 Experimental evidence as to this function has been obtained with living Halistemma 

 at Naples. In Crystallodes the circular muscles round the horns of the bell-cavities 

 were seen to be connected by two nerves to two symmetrically dispo ed diverticula 

 projecting from the lateral gastrovascular canals into the jelly body. These have 

 not hitherto been described, though in the youngest swim-bells near the apical air-sac 

 they are relatively quite large and easy to see. In the older swim-bells they are 

 reduced to mere pin-points. It is suggested that these organs serve as differential 

 pressure gauges, and that it is by their means that the directive propulsive mechanisms 

 of the animal are regulated. 



10. Dr. R. T. GuNTHER. — The Collections of the Tradescants, Poynter, Dyer, 



and Clutton. 



These very early collections of objects of Natural History, though greatly reduced 

 by neglect, not only include some of the oldest museum specimens known, but, taken 

 together, illustrate in a unique manner the early history of museums in Great Britain. 

 A few of the specimens that have survived the wear and tear of centuries have now 

 been brought together for the first time in our oldest public-museum building. 



1. The John Tradescants, father and son, collected from 1627 to 1656. They 

 founded the first London museum at Lambeth, and by their endeavours provided an 

 incalculably great incentive to the exploration of the world by stimulating traders 

 and travellers to take stock of the interesting and valuable produce of foreign countries. 



The contents of their museum were transferred to the Old Ashmolean Museum in 

 Oxford in 1683, where they remained until 1860, when they were scattered. The 

 gradual process of destruction of the historic specimens has been continued almost 

 to the present day, and unless special care be taken of the few specimens that remain 

 more will disappear. The specimens stiU extant represent some fifty species of 

 animals, and m the opinion of many authorities should once more be brought together 

 and be conserved as a collection. 



2. John Poynter, chaplain of Merton College, made a general collection of naturalia, 

 animal, vegetable, and mineral, for the purpose of illustrating his lectures to his pupils. 

 It is probably the oldest teaching collection, and without equal in Britain. Since about 

 1730 it has been in the possession of St. John's College, and although many specimens 

 have perished, it has been possible, by good fortune, to save the remainder, in the 

 original drawers. Of unique interest are the series of British birds' eggs representing 

 some forty species, perhaps the only evidence for the existence of certain varieties of 

 colour markings as long ago as the year 1700 ; a series of the rocks of Shotover HiU, 

 perhaps the oldest stratigraphical collection of rocks now preserved to us ; typical 

 series of minerals, fossils, and botanical specimens. The latter include an early series 

 of Barbadian nuts and seeds given by Edward Dyer, a highly skilled botanist, fellow 

 of Oriel CoUege, 1673. 



3. The Clutton collection usefully supplements available scientific evidence as to 

 the species of animals and plants used in medicine at the beginning of the eighteenth 

 century. Other old collections of materia medica are less complete, or are not beyond 

 suspicion, including substituted specimens of recent date. 



Joseph Clutton, an apothecary of repute living at tlie Turnstile in Holborn, sold 

 the entire collection of 1,032 specimens in a cabinet in 1729 to a Thomas Jobber for 

 £21 6s. M. It became the property of New College at the death of Warden Oglander, 

 and has been in cold storage in the muniment-room of that college ever since. 



