TRANSACTIONS OF SECTION D. 653 



characteristic feature being the presence of a large digestive vacuole occupying 

 the anterior middle fourth of the body, and lying above but not in immediate 

 continuity with the mouth. 



No vagina or spermotheca is present, the ova being extruded by the rupture of 

 the cuticle at a short distance in front of the penis owing to an ever-increasing 

 growth pressure. 



In some points this turbellarian resembles Bbhmigia ; it possesses, however, no 

 female accessoria ; a similar absence obtains in the genus Haplodiscus, from which 

 also it ditfers in the following not unimportant details : — 



(1) Shape. 



(2) Parasitic habitat. 



(3) Mouth situated in the anterior fourth. 



(4) Paired testes in the lateral parts of the body. 



(5) No defined vasa defereutia. 



(6) Penis with chitinous knob-lilce armature, 



(7) Presence of a large dorsal vacuole. 



Attention is drawn to the present classification of the Acoela. It is suggested 

 that the family Propovidcc, comprising all Acoela with one genital opening, bo 

 subdivided into two sub-families. 



(1) P/'o;oo)-iw.c<?, including the genera (a,) Propoms, ih) Monopovus, {c) Bdhmi(/ia, 

 i.e., those Acoela with a common genital atrium. 



(2) Avar/inince, consisting of («) Haplodiscus and (6) the genus presently 

 described, these having male accessoria only. 



TUESDAY, SEPTEMBER 16. 

 The following Papers were read : — 

 1. Some Remarks on the Atlantis Problem. By R. F, Scharpf, Ph.D. 



Since the dawn of early history the question of the existence of a continent 

 beyond the ' pillars of Hercules ' has occupied the mind of man. Our very earliest 

 records of this mythical land were derived from a narrative which has been 

 handed down to us by Plato. According to it, Solon is said to have visited Sais 

 in Egypt, and there to have beard from priests of the ancient ' Empire of 

 Atlantis ' and of its overthrow by a convulsion of Nature. This Atlantis was 

 then spoken of as a vast land lying beyond what we now call the Straits of 

 Gibraltar, and it is supposed to have been inhabited by a mighty race of people. 

 Plato's story has called forth quite a Hood of literature, not only in ancient times ; 

 even within the last score of years many pamphlets and books have been pub- 

 lished dealing with this attractive problem. Some authors have sought to 

 discredit the veracity of Plato's assertions, while several, and among them 

 Humboldt and Sir Daniel Wilson, were of opinion tliat the tale rests on some 

 historic basis. Others again have utilised the original story and connected it with 

 their own ideas of a land-bridge stretching right across the Atlantic from Europe 

 to America. 



The Atlantis problem, however, was only raised to scientific importance when 

 modern research revealed the fact that the living as well as the extinct flora and 

 fauna of Europe have quite a number of types in common with North America. 

 Unger was the first to put forward the view, from a purely scientific reasoning, 

 that the Atlantic Islands, that is to say, the Azores, Madeira, and Canary Islands, 

 formed part of a land-connection Avhich stretched right across the Atlantic and 

 still preserved some of the plants which invaded our Continent from the New 

 World. Heer hailed this hypothesis with delight, while Andrew Murray adopted 

 it in a somewhat modified form. Edward Forbes also occupied his fertile mind 

 with the problem, but could not convince himself that the vast laud which 



