DUBLIN NATURAL HISTOBY SOCIETY. 155 



Dublin in a small tin box packed in wet sand remarkably well, and has 

 since been kept in a small vivarium.* 



This crab has given rise to some discussion as to whom the priority 

 of its discovery in Ireland is due. Having been lately looking over the 

 back Transactions of this and other Societies, I find myself in a position 

 to clear up much of the mystery of this " knotty" point. I hope, there- 

 fore, it will not be considered to be trifling with the time of the Society 

 if I lay before them the results of these investigations, 



Thia polita was first detected by that indefatigable collector, "W. 

 M'Calla, in Eoundstone, in 1845 ; he failed in identifying it, as the fol- 

 lowing extract from a paper read by Dr. Charles Earran before your 

 Society, January, 1845, proves : — 



" This winter I have added two species, Portunus marmoreus, I have 

 not been able to determine the genus of the other : one thing is certain, 

 it is new to Britain, if not to science. The undetermined species was 

 found in shallow water, at extreme low water-mark ; I obtained five 

 specimens. Having paid considerable attention to the Crustacea, I had 

 no hesitation in writing to Dr. Scouler that I had been so fortunate 

 as to have added a new genus to this department." — Saunders' News- 

 letter, January 9, 1845. ( Vide also Report of Dublin Natural History 

 Society for 1844-45, p. 17.) 



The species was subsequently identified, and published by Pro- 

 fessor Scouler, in a paper laid before this Society in January, 1846, 

 as the following shows : — "Dr. Scouler then brought forward the dis- 

 covery of, and addition to, the British Crustacea of Thia polita. This 

 remarkable and beautiful little crab was found near Roundstone, Conne- 

 mara, by Mr. M'Calla, where it burrows in sand ; only one species of the 

 genus is described as European, and this discovery is an important ad- 

 dition to the Crustacea of Britain. A very fine female specimen was 

 exhibited from the Museum of the Society ; a smaller one, a male, is in 

 the collection of the Dublin Society." — Saunders' Newsletter, January 9, 

 1846. Vide also Eighth Report of Dublin Natural History Society, p. 8. 



M'Calla himself also brought the discovery before one of the Evening 

 Meetings of the Royal Dublin Society, held 28th of February, 1846. 

 ( Vide Proceedings, Royal Dublin Society, vol. lxxxiii., Appendix xv., 

 p. cxiii. ; and vol. lxxxii., Appendix v., p. xlv.) This last paper purports 

 to have been read on the 10th of January, 1846, but must have been 

 corrected subsequent to this date. Professor Scouler, furthermore, pre- 

 sented specimens to the British Museum, as appears by reference to their 

 Catalogue published in 1847. 



By some mischance or other, however, it escaped the notice of English 

 naturalists, and when in 1850 Professor Melville, ignorant of its previous 

 occurrence on our shores, met with the species in Galway, he, having 

 first identified it from the description given by Milne Edwards, for- 

 warded specimens to Professor Bell, by whom it was published as an 



* Still alive and healthy, although now three months in confinement — June 28, 

 1857. 



