152 DITBLIK NATURAL mSTOET SOCIETY. 



being a colony solely female, met with under any cifcumstdncies. I would now 

 beg to observe that I cannot make all my specimens agree with the description 

 given by Forbes and Hanley, who say of this shell — " The suture is distinct, but 

 simple, and never canaliculated," — and I have the pleasure of laying before you 

 a series exactly answering to this description. I have also selected another, in 

 all of which, from the young up to the adult, the suture is strongly marked, and 

 I think I should be justified in stating that it is slightly canaliculated. In addi- 

 tion to this, as far as I have observed, the shell grows to a larger size, is hea- 

 vier, more spiral, the whirls more globose, and it is often more closely striated. 

 I beg to lay this series also before you, in order that you may judge of the cor- 

 rectness of my observations. I would suggest, though with much diffidence, that 

 there are sufficient distinguishing characteristics in this second series of jan- 

 thinie to entitle them to be made, at least, a variety of the species Communis. I 

 had written thus far, when I was much gratified by accidentally finding that my 

 views — though not, as I imagined, original— agreed with those adopted by Forbes 

 and Hanley, in the Appendix to their work on the British Mollusca, as in it 

 they figure a janthina closely approximating to those in my second series, re- 

 specting which they write, that — "Until the genus Jjlnthince shall have expe- 

 rienced a thorough revision, and the eff'ect of local circumstances in producing 

 variation of colouring, chasing, and contour upon its migratory members^ shall 

 have been duly estimated, it will be hazardous to define the limits of the s'everal 

 varieties or species which by the past generation of conchologists were included 

 in the Helix janthina, by the present in the J. fragilis or communis." Krauss, 

 in his useful work on the Testacea of Southern Africa, remarks, " That the in- 

 digenous shell figured by Chemnitz is very distinct from the Neapolitan one 

 termed bicolor by Philippi, though both are usually cited as identical. Our Bri- 

 tish examples, again, seem different from either, and were considered so by Dr. 

 Leach, who, we are informed by Mr. Jeffreys, termed them Britannica." Refer- 

 ring to this plate, which, I might mention, is taken from an Irish example, they 

 say, that " It differs from those previously described in so many particulars 

 that it becomes of importance to specify them." But I will not introduce that 

 description here, as I have not given a detailed one of that which I consider to 

 be truly entitled to the specific name Fragilis. It is only just for me to mention 

 that they, in conclusion, express some doubts as to its being admitted as a dis- 

 tinct species, inasmuch as they remark that " A more than ordinary latitude 

 seems permitted to shape in this species, because the larger turns do not always 

 strictly coil in a regular spiral, but, sometimes deflecting, attach themselves 

 below the periphery, in which event the spire is wont to become more elevated, 

 and its more rounded turns to swell out in some degree above the suture." I 

 hope I have succeeded in establishing sufficiently good claims for this shell to 

 induce naturalists to give it a more attentive investigation ; and it is a subject 

 of so much interest that it will, I think, amply reward them. At the same time, 

 as I before observed, I obtained Janthina pallida. This very rare species has 

 only twice before been found on our coasts — once at Miltown Malbay and once 

 at Kilkee. The specimens of Spirula Peronii which I found were all dead. This 

 beautiful shell has only, I believe, occurred five times on the Irish coast, and but 

 once in England, on the Cornish coast. It has been provisionally excluded from 

 the list of British Mollusca, ** because," as Dr. Fleming observes, *' we have to 

 determine their capability of living in our seas before their right to a place in 

 our Fauna can be estabfished." Lar^e numbers of the Velella were also thrown 

 ashore in company with the Janthinae. When floating on the surface, with the 

 sail or membrane drifting before the wind, they present an interesting spectacle, 

 which I observed to advantage when rowing in the bay in one of the small ca- 

 noes or corachs peculiar to the west coast of Ireland. The vellela, when cap- 

 tured, throws off a very deep purple viscous liquid, which stains the hand much 

 more intensely than that exuded by the janthinae ; indeed, I believe some natu- 

 ralists have expressed it as their opinion that it was probably from devouring 

 tbese VeleW» the purple colour of the Janthina was derived. I omitted men- 



