388 Mr. W. Thompson's Additions to the Fauna of Ireland, 



Borlasia octoculata, Johnst. id. p. 537. pi. 18. fig. 2. 

 A few specimens agreeing in size and all the characters with the 

 description and figures w T ere obtained with the last. 



Borlasia purpurea, Johnst. id. p. 537. pi. 18. fig. 3. 



This species, differing little from the last in any external character 

 but that of colour, was procured at the same time, but was much more 

 numerous. Several specimens of this and the other species of the 

 same family here noticed were kept alive for three weeks in a phial 

 of sea- water, and thus afforded ample opportunity for observation. 

 The water was not changed daring that period, but the length of 

 time that they would have lived under such circumstances was not 

 ascertained, in consequence of my leaving home. The individuals 

 of this species were about 3 inches in length and perfectly agreed 

 with the description and figures : some had only six, and others eight 

 eyes as stated by Dr. Johnston. 



Borlasia olivacea, Johnst. id. p. 536. pi. 18. fig. 1. 



A worm agreeing in all characters of form and colour with this — 

 having four eyes, and marked with red over the site of the heart ; 

 characters specially named as they are apparently not constant — 

 was procured between tide-marks in July 1846 at Bangor, Down- 

 shire, by Mr. Hyndman and myself. A specimen agreeing with this, 

 except in having eight eyes, was taken with the species noticed as 

 obtained at Strangford Lough in June, but, judging from zoological 

 characters only, I could not think that it was distinct from B. 

 purpurea. 



Planaria lactea, Mull. Zool. Dan. vol. iii. p. 47. pi. 109. figs.l, 2 ? 



This species is marked with doubt from the circumstance of its 

 differing in the following characters from P. lactea. The chief central 

 vessel represented in the figure as of about equal breadth throughout, 

 expands in this into an ovate form about the centre of the body — 

 and the ramifications from it, represented as purple in P. lactea, are 

 in this of a rich fawn-colour. My specimens are 9 lines in length, 

 when the breadth is 2 lines ; eyes pyriform, generally two in num- 

 ber, placed as in P. lactea (a specimen had two at one side, and 

 one eye at the other) ; colour milk-white, but the main vessel and 

 its ramifications, spreading throughout all the body except the mere 

 margin, imparts a handsome delicate fawn-colour to the animal. All 

 of the many specimens taken were of the same colour ; the size al- 

 ready noted marks them as considerably larger than Miiller's. When 

 in motion they were generally more elongate (of about equal breadth 

 throughout) than P. lactea is represented to be, but occasionally 

 appeared of the same form as the figure in the ' Zoologia Danica/ 



During an excursion round the shores of Lough Neagh at the be- 

 ginning of August 1846, when I was accompanied by Mr. A. H. Ha- 

 liday, this species was found to be very common, attached to stones 

 at the margin of the lake, and to subaquatic plants. It was grega- 



