Philip : The Finding of a Famous East Yorks. Diatom. 215 



Recently, among" some papers left by the late Mr. Harrison 

 and handed to the writer for examination, were found a number 

 of letters from Dr. Walker Arnott, of Glasgow, from which one 

 may gather in an indirect manner (like overhearing half a con- 

 versation by telephone) some interesting particulars respecting 

 this discovery. It appears that Mr. Harrison, while taking 

 a walk across the fields near the remains of the ancient Priory 

 of Haltemprice, observed a spring welling up from the ground 

 in a little sandy basin, the sand in continual motion, thrown up 

 by the bubbling of the rising water. It occurred to him to take 

 some of the sand home for microscopic examination, and he 

 was greatly surprised to find the granules were coated with 

 numbers of diatoms, having a cruciform vahe, marked with 

 radiating striae and a bale-shaped side view, as well shown in 

 Smith's figures here reproduced. 



Fragilaria Harrisonii on a Sand Grain. 



This form was quite unlike anything Mr. Harrison had pre- 

 viously found, and he consulted with Mr. Sollitt, to whom it 

 was also a novelty. At first they supposed they had got 

 TetracycliLs laciistris, an alpine form found in Scotland and the 

 Lake District. This does not say much for the definition of 

 their instruments, as the two forms have nothing in common 

 save a general resemblance in the outline of the valve view. 

 Both the Hull diatomists were at that time in correspondence 

 with Dr. Arnott, who was a leading authority of that day, and 

 they forwarded a slide of the new discovery to him for 

 identification. Dr. Arnott appears to have been equally puzzled. 

 He writes to Mr. Harrison that he has sent the ' Tetracylus ' 

 to the Rev. Wm. Smith (the author of the Synopsis) and adds : 

 ' It may be that species, but I hope it is something new. It 

 seems to me rather liker the genus Odontidium' 



1904 July I. 



