﻿Prof. Milne — Across Europe and Asia. 557 



two may be separated. Fig. 19 represents the specimen originally 

 figured by Prof. Seeley, which is lent to me by the kindness of the 

 Curator of the Woodwardian Museum. Fig. 21 is a drawing of 

 Crepidula alta, Seeley, which still remains an unique and perhaps a 

 distinct shell, although I hesitate to accept it as such in a group, the 

 individuals of which are liable to such extreme variation. Curious 

 instances of this variation occur in the apertures of Fusus longoevus 

 from the Paris Basin, in the British Museum, in which Capulidce are 

 flattened and even take the crescentic form of the aperture of that shell. 



Fig. 3a represents Crepidula gaultina, considerably enlarged and 

 looking down upon it, and shows the helicoid apex which Dr. J. 

 Gwyn Jeffreys notices as being common to all the limpets. In this 

 species it is especially persistent, and is very distinctly visible in tlie 

 cast, and also, but less so, in the perfect shells from Folkestone. 



Fig. Qb is the apex alone, and shows the fine transverse ribbing 

 with which it is always internally ornamented. Figs. 6a, 8a, 86 

 are other views showing the position of the helicoid apex, but are 

 enlargements of shells said to be Calyptrcea GooJcsonice. Fig. 4a is a 

 view looking down upon C. gaultina. Fig. 4& shows the crater-like 

 scar, highly magnified, which is left on the cast after the removal of 

 the helicoid spire. This is the imperfect state in which most 

 specimens are found. 



The great variety of scar left after the removal of the septum 

 is well seen in this series. As I am informed by Mr. Jesson and 

 the Rev. Arthur Buxton that the casts of these shells are abundant, 

 when diligently searched for, in the apertures of Cephalopods in the 

 Cambridge beds, there will be no difficulty in confirming the correct- 

 ness of my proposal to unite the several forms in a single species. 

 In this case Buvignier's name would have priority. 



Fig. 22 represents Bracliystoma angidaris, Seeley. The genus was 

 proposed by me in this Magazine last year to receive this rare shell, 

 and is placed in the family of Aporrhaideg. I had then no space to 

 figure the Cambridge specimens (two in number), which are now 

 in the Woodwardian Museum, and I embrace this opportunity of 

 figuring one of them, as they are of larger size than the still unique 

 specimen from the Gault of Folkestone. 



VI. — Across Europe and Asia. — Travelling Notes. 



By Professor John Milne, F.G.S. ; 



Imperial College of Engineering, Tokei, Japan. 



(Continued from p. 518.) 



VII. — Irkutsh to Lake Baikal. 



Contents. — Irkutsk; its Earthquakes — Gold- washing in Easteiji Siberia — Method 

 of sinking to the bottom of a river through a shaft of ice — Eoad to Lake 

 Baikal — Bound its southern end — Old lake-terraces — Its former extension — 

 Origin of its basin — Bearing of its Fauna on its origin — Is it a pool left behind 

 a flood ? 



WHILST in Irkutsk I had many opportunities of conversing 

 about the earthquakes which sometimes disturb these Central 

 Asian localities. Not long before my arrival in the town, a sharp 

 shocks had been experienced. The general effect it produced was 



