Bfl Mr. Thompson on the Mollusca of Ireland. 



pretty rounded termination which the tubercles of D. bila- 

 meliata generally present, are fasciculi of spicula, and these 

 not so tastefully disposed over the surface of the cloak as in 

 that species : in all respects it is a less attractive animal. 



In the month of December 1837, I obtained three speci- 

 mens of this Doris from among oysters dredged at Green- 

 castle, county of Londonderry. 



Doris bilamellata, Linn. Johnst. Ann. Nat. Hist. vol. i. 

 p. 5.3. pi. 2. fig. 8. D. verrucosa, Penn. 



I have obtained this between tide-marks, at the island of 

 Lanibay, off the Dublin coast, and by dredging in about ten 

 fathom water, in Belfast Bay. A specimen which was particu- 

 larly examined, was found to agree with Dr. Fleming's de- 

 scription of D. verrucosa in the number of branchial processes, 

 which are 2 1, and in their arrangement being somewhat "se- 

 micircular/* in a broadly horse-shoe form, thus Q. In Dr. 

 Johnston's specimens, the branchial processes seemed "not 

 much to exceed twelve," and were disposed in an " uninter- 

 rupted circle." Annals, vol. i. p. 55. Although the precise 

 number of these organs is of no specific value, the difference 

 alluded to is so great as to be worthy of attention. In a 

 specimen from Newhaven, near Edinburgh, favoured me by 

 Mr. E. Forbes, these processes are twenty in number. 



Doris muricata, Mull. Zool. Dan. vol. hi. p. J. tab. 85. 

 f. 2—4. 



I have not unfrequently taken this minute species when 

 (accompanied by Mr. Hyndman,) dredging in the loughs of 

 Strangford and Belfast; it was generally adhering to the 

 leaves of tangle (Laminaria digit ata). Muller describes it as 

 5 lines long by 3 broad : my specimens were all even under 

 this size. The D. muricata has hitherto been unnoticed in 

 the British seas. 



Doris pilosa, Mull. Zool. Dan. vol. iii. tab. 85. figs. 7 

 and 8. Johnst. in Ann. Nat. Hist. vol. i. p. 54. pi. 2. figs. 9 

 and 10. 



The first Irish specimen of this Doris that I have seen was 

 found in Dublin Bay, by G. J. Allman, Esq., to whom I am 



