i897-] Adams. — Paludestrina \Hydrobid\Jenki71sh Smith. 235 



men-of-war, which afterwards fought against the Armada, 

 were built near Topsham on the very spot where P. Jenkinsi 

 now flourishes. They must have been vessels of very small 

 draft to have navigated the Exe at all, though the river may 

 have been deeper then. Between 1840 and 1855 there was a 

 regular trade between St. Petersburg and Finland and Tops- 

 ham in timber, &c., but this trade ceased some twenty years 

 ago, the timber being now unshipped at Kxmouth, and sent to 

 Exeter by rail or canal. 



Sandwich, too, in former times, imported timber from the 

 Baltic, as well as from other places, and this trade continued 

 till quite recently, when the improved harbours of Dover and 

 Ramsgate killed it. Along the south bank of the Thames 

 timber has been unloaded from the Baltic, and other places, 

 from time immemorial. 



Now, the fact of the same foreign locality exporting 

 timber to three different British ports (the only known 

 habitats (then) of the species in question), and that same 

 foreign locality being the only one, so far as I have been able 

 to ascertain, trading mutually with two out of the three seemed 

 a curious coincidence, and one which formed a plausible 

 hypothesis. I ascertained that Newhaven and Wisbech also 

 imported timber from the Baltic, and I suggested that search 

 should be made there. I made two excursions to Wisbech 

 and neighbourhood, but I had very little time to search the 

 far-extending dykes thoroughly, and I failed to find it. How- 

 ever, in 1894, Mr. C H. Morris, of Eewes, found an exceedingly 

 abundant colony at Newhaven. Curiously enough Mr. Morris 

 and several others had worked the locality for several years, 

 and had never met with it before. Hearing that Baltic 

 timber was still unloaded at Rye, I searched for the shell 

 there, but my limited time again prevented me from investi- 

 gating the many miles of dykes that intersect the plain round 

 that charming old Cinque Port. However, I did find it close 

 by in the Military Canal at Hythe, which is joined to the Rye 

 dykes by sluices in several places. In 1893, Mr. A. T. Daniel, 

 of Stoke, found a thriving colony in a Staffordshire canal, 

 near Dudley, which was the first inland locality noticed ; but 

 I have been unable to obtain any information respecting this 

 spot, though probably there is a timber wharf not far off. 



