JACKSON: ATTEMPT TO BREED FROM A SINISTRAL HELIX POMATIA. 343 



From this date the snails became very inactive, often spending 

 weeks at a stretch suspended from the cover-glass of tank by a thin 

 film of white mucous round mouth of shell. One or other of them 

 would occasionally crawl round tank, and once I noticed S. had 

 turned back its head, and was gnawing the lip of its shell, in the same 

 manner as I had seen Z>. doing early on in the year. 



On October 4th I put both snails away in a wooden glass- 

 lidded box, with soil at bottom, to hibernate. I examined them again 

 on November 24th, and noticed that 6". had formed a thin white 

 opaque film within the aperture of the shell. This was stretched tight 

 across, and in the middle there was a thick strip of mucus by which 

 the shell was suspended from the glass. At the junction of this strip 

 with the white epiphragm there was a dark red blotch resembling 

 blood. The white film mentioned above was not the usual winter 

 epiphragm this species makes, but was quite thin, and more like parch- 

 ment. This may have been brought about by keeping the snails 

 indoors, as I can hardly see that it could be from want of lime, as I 

 kept box and tank well supplied. 



On March 12th, 1905, I noticed Z>. had formed a thin white 

 epiphragm, like that of S., but much further in the shell. On April 

 1 6th, I cleaned out the old tank, and prepared it again for the snails. 

 About an hour after I had put them in I noticed that S. had revived, 

 and was crawling about and eating freely; D., however, remained 

 dormant, 



I put in some fresh food on April 3olh, and as Z>. was still dorm- 

 ant, I took it out and examined it, and found the epiphragm was 

 broken, the snail evidently having been out. On touching a portion 

 of its foot, which was protruding from the shell, it made very feeble 

 movements. On May 9th I found Z>. dead ; S. was in good con- 

 dition and fairly active. From this date onwards there was nothing 

 special to record, as my experiments were practically at a stand-still. 



I wrote to several friends for living Helix po/nafia, but it was not 

 until September 17th that I received several specimens, through the 

 kindness of Mr. A. G. Stubbs. These I introduced to the tank, and 

 they at once commenced to crawl round, being afterwards joined by 

 S. S. looked very thin, and crawled along with difficulty. On look- 

 ing closely at it, I noticed an injury to the edge of the mantle, and 

 that G.o. was much swollen and protruding slightly. It did not live 

 long after this, for on going to the tank on Sept. 24th 1 found it dead. 



I was keenly disappointed at this loss, as I had prepared for photo- 

 graphing by flashlight the extremely curious and interesting move- 

 ments observable in the snails during lovemaking. Early on in their 

 attempts at pairing, not having a camera at the time, I made one or 



