Stkphions — The Fresh-water Sponges of Ireland. 21n 



Tho description of the fragmeiitB of sponge doubtfully ascribed by 

 Hanitsch to E. crateriformia agreed so well with poorly developed specimens 

 oi Heteromei/enia Byderi (41, \>. (i) that a visit was paid to Park T.ough in 

 August, 1917, in the hope of definitely settling the question of the identily 

 of the sponge from this locality. Park Lough is a very small lake, lying on 

 the lower south-western slopes of Hungry Hill, at an altitude of 300 feet. 

 It has boggy shores, with steep turf banks at the western end, and a few 

 stones lie on the soft peaty bottom at the eastern end. The lake thus does 

 not present favourable conditions for the growth of sponges ; but a thorough 

 search along its shores resulted in the finding of a fair number of small 

 specimens. These were growing for the most part on the under surface of 

 stones that were laid loosely, one on top of the other, stretching out from the 

 shore to form a sort of rough pier under the water. Three or four specimens 

 were found on the stems and roots of water-plants. Similar specimens were 

 found a little way down the stream, draining the lake, where a stony bottom 

 afforded some suitable ground for sponges. All the specimens obtained were 

 very soft in texture, yellowish iu colour, and tended to be slightly lobed ; in 

 other words, externally they agreed exactly with poorly developed specimens 

 of HeUromeyenia Byderi, such as one would expect in an unfavourable habitat. 

 About this time a minute fragment of the original material, collected in 

 Park Lough by Dr. Scharff in May, 189o, was discovered among the sponges 

 preserved in the National Museum. A comparison of the spicules of this 

 sponge with those of the specimens recently collected proved that they all 

 agreed exactly with Hanitsch's description of his doubtful E. cratcriformis. 

 Fully developed gemmules were not present, but a few scattered amphidiscs 

 were discovered which proved beyond doubt that the sponge was a form of 

 Heteromeyciiia Byderi with slender spicules, such as occurs where the 

 conditions are not favourable to a vigorous growth. In addition to the 

 developing amphidiscs figured by Hanitsch (21, fig. 5), a very few mature 

 amphidiscs of both kinds were found in the fragment collected in 1893. 



Specimens of Truchospongilla pennsijlvanica and Spongilla cratenfm-mis 

 from North America, identified by Potts, and a specimen of the latter 

 species from India, were available for examination. In this connexion it is 

 interesting to note that the two North American species which have to 

 be deleted from the Irish list have, within recent years, been found iu 

 India (3). 



The supposed occurrence of Trochospongilla pcnnsylvanica in Scotland may 

 also, perhaps, be referred to in this place. 



Some years ago Ur. Annandale (2) collected two species of sponges in 

 Loch Baa, in the Island of Mull, Scotland. One of these was a form of 



