270 JOURNAL OF CONCHOLOGY, VOL. I5, NO. 9, MAY 1ST, I918. 



bandless, the more dominant such would prove to be. In the above 

 experiment tlie appearance of shells with the second band absent, 

 bred from five-banded parents, is distinct evidence against such a 

 universal supposition. 



Experiment No. 2. Helix nemoralis L. 



Commenced in April, 1910, with two specimens collected in a wood 

 near Kiltoom, Co. Roscommon. Both specimens were of a pale 

 pinkish red colour, which for the want of a better name I shall call 

 carnea; one specimen possessed a band formula 12345, all the bands 

 being much interrupted and almost reduced to spots (a very common 

 feature in specimens found in the central districts of Ireland); in the 

 second specimen the third band was well developed and there were 

 distinct traces of the fourth and fifth; all three bands showed a 

 tendency to be spotted. We may refer to both the originals, therefore, 

 as caimea-interrupta. 



The Fi generation was born in June, 1912; many died, but 37 

 reached an age sufficient to leave no doubt as to their colouring and 

 banding. Of these eleven were libelhda and twenty-six carnea; one 

 (Jibelluia) was bandless ; ten had five bands (five libelhda and five 

 carnea) ; twenty-six had three bands, 00345 (five libelhila and twenty- 

 one carnea). In the case of three only (all carnea) were the bands 

 continuous, the remaining thirty-three banded shells all possessing 

 the interrupted bands. The experiment ends here, owing to some 

 disease 'Attacking and destroying the whole Fi generation before any 

 reached maturity. 



The chief facts of interest are, firstly, the appearance of libellula 

 shells from carnea parents, pointing to the supposition that yellow is 

 recessive to red. Secondly, the appearance of a bandless shell from 

 two banded parents. As stated in the last experiment. Prof. Lang's 

 researches led him to conclude that bandlessness was dominant to 

 handedness, and in most cases this would seem to be true. I would 

 like to put forward the suggestion here, however, that besides the 

 dominant bandless state there may be also a recessive one, both being 

 similar in outward appearance. The latter might be due to the 

 absence of the factor necessary to produce the banding, the former to 

 the presence of an inhibiting factor preventing the bands' appearance, 

 even though the factor to produce bands were present and these 

 might become apparent in the succeeding generation. 



The fact that all H. nemoralis are hatched from the egg in a band- 

 less state might be taken to signify that this was the primitive type of 

 the species, according to the law of recapitulation. It may be 

 opportune to mention here the order in which, accorduig to my 

 observations, the different bands appear in the young shells. The 



