ON THE MORPHOLOGY OF THE HELIClNIDJi. 759 



patches by digging holes to lay their eggs ; so they asked the 

 Shark to take the Megapodes away. This was done, but now the 

 natives missed the Megapodes" eggs, so they asked the Shark to 

 bring the Megapodes back but to confine them to one spot. 

 This request was also complied with, and the result may now be 

 seen. The Megapodes lay their eggs in two large and broad 

 sandy spaces, and nowhere else on the island. 



I suspect that there is more than a grain of true history in 

 this legend, and that it records the fact that when the ancestors 

 of the natives came to the island, they brought with them two 

 raaiii staples of their food-supply — yams and Megapodes. 



35. Contributions to the Morphology ut* the Group Neritacea 

 of the xVspidohranch Gastropods. — Part II. The Heli- 

 ciNiD.^. By Gilbert C. Bourne, M.A., D.Sc, F.R.S., 

 F.Z.S. 



[Received April 29, 1911 : Read May 9, 1911.] 

 (Plates XXX.-XLII.*) 



When, two years ago, the Society published the first part of my 

 contributions to the morphology of the Neritacea (2), I had already 

 accumulated a number of observations on the anatomy of the 

 Helicinida?, but deferred the publication of them until I was able 

 to obtain specimens of difteient species from various parts of 

 the Pacific region. Having experienced considei'able difficulty in 

 obtaining specimens sufiiciently well preserved for microscopical 

 examination, the publication of my results has been long delayed, 

 with the result that I lose the cltiim to priority for several minor 

 discoveries concerning the anatomical features of this family, for, 

 in the meantime, Thiele (10) has given an account of the anatomy 

 of Hyclrocena cattaroensis in which is included a description of 

 the female generative organs oi Helichia kuharyi, and the following 

 descriptions lose much of the novelty they Avould have possessed 

 had they been published as soon as the facts were ascertained. 



Previous to the publication of Thiele's paper, our knowledge of 

 the anatomy of the Helicinidne rested, for the most part, on 

 Isenkrahe's (4) account of the anatomy of Helicina titanica. 

 Isenkrahe gave a sufficiently accurate description of the external 

 anatomy, the muscular system, the greater part of the alimentary 

 tract, and the pulmonary cavity, but he failed altogether to 

 distinguish the kidney, and his descriptions of the heart, the 

 nervous system, and the reproiluctive organs are defective. These 

 imperfections notwithstanding, Isenkrahe was able to confiiiu 

 Troschel's opinion that Helicina, on account of its rhipidoglossate 

 dentition and other anatomical characters, was closely related to 

 the Neritidaj. 



Von Jhering (5) in 1877 placed the Helicinacea and Proserpinacea 



* For explanation of the Plates see pp. 806-809. 



