HUDSON : MOLLUSCA OF THE LOWER TEES. 47 



gradually passes by almost insensible degrees of colouration 

 into a sub-variety somewhat approaching var. leucozona 

 Taylor. 



H. virgata var. subalbida (Poiret). — Occurs sparingly with 

 var. albicans. 



H. caperata var. fulva Picard. — I have taken a few specimens 

 on Redcar Sand Hills, which I think are referable to this 

 variety. 



Another variety somewhat more abundant occurs 

 between Marske and Redcar on the sea banks, and also at 

 Coatham. It is entirely without trace of banding, of a dirty 

 white or yellowish hue with the apex black as in the type. 

 In form, the shell is variable, but in general, resembles the 

 type. I have not seen any varietal description which agrees 

 with this. 



Zonites nitidulus var. Helmii (Alder). — I have taken this 

 pretty variety in a lane leading from the Spring Gardens to 

 Marske Road, between Redcar and Marske. Though not 

 uncommon it is exceedingly local, being confined to about 

 fifty yards of a somewhat dry ditch. 



Succinea elegans Risso. — Until last year this species was 

 moderately abundant in a ditch near Coatham brick ponds, 

 but the ditch has now been enlarged and deepened and I 

 am afraid the species will be lost to the locality. 



Limnaea peregra var. lineata Bean. — Two or three of this 

 variety have occurred to me at Marton. 



L. peregra var. acuminata Jeff. — Common in brook run- 

 ning from old fish ponds at Kirkleatham. 



L. truncatula var. ventricosa Moq. — Pond near Normanby. 



Planorbis albus Mull. — Not uncommon in old fish ponds at 

 Kirkleatham. 



Physa fontinalis var. oblonga. — Coatham Marshes. 



The slugs of the district seem very variable and but 

 little has yet been done with them, I however append a 

 list of those species and varieties not mentioned by Mr. 

 Ashford. 



