398 Proceedings of the Boyal Physical Society. 



these worms are are constantly being removed into other 

 cooler houses for a time, yet after a little the worms die out 

 or disappear in the lower temperature. The hotter the house, 

 the livelier they always are ; in the house where there is a 

 large bed of soil, with a tank of hot water under, they are 

 extra lively. They are far worse than the common earth- 

 worms for working in flower-pots, choking up the drainage, 

 and they seem to ramble about a great deal at night. I have 

 no doubt they were first introduced into the houses here in 

 the soil amongst the roots of orchids, or other foreign plants. 

 They are very numerous, but very difficult to capture, as they 

 are so quick in their movements. Whenever a pot is turned 

 out, they at once retreat into the centre of the ball of earth, 

 and cannot be got out without shaking out the roots of the 

 plant." 



XXXV. A Revised List of British Echinoidea.^ By William 

 E. HOYLE, M.A. (Oxon.), F.R.S.E., Keeper of the Man- 

 chester Museum. 



(Read 20tli March 1889.) 



The British collector has no memoir to which he can 

 turn for the identification of the sea-urchins he may obtain 

 more recent than the classic monograph of Edward Forbes, 

 published forty-eight years ago. The admirable revision of 

 the Echinodermata, drawn up in 1865 by the Rev. Canon 

 Norman, unfortunately stopped short of the Echinoidea, and 

 his numerous engagements, and the continually increasing- 

 demands upon his time made by the charge of his invaluable 

 collection, have hitherto prevented him from completing the 

 work. 



The present paper owes its existence to a combination of 

 circumstances. The Fellows of this Society will remember 

 that in 1883 I contributed to our Proceedings (vol. viii.) a 



^ This catalogue was drawn up now more than a year ago, but various 

 circumstances have combined to retard its appearance. This delay has been 

 in several respects fortunate, and not least so in that it has made it possible 

 to utilise Prof. Martin Duncan's "Revision of the Echinoidea" (Journ. Linn. 

 Soc, xxiii., 1889).— W. E. H., June 11, 1890. 



