PROCEEDINGS OF THE SOCIETY. 127 



Mr. F. W. Watson Baker said that he had brought for exhibition a 

 series of sixteen specimens illustrating the development of an Ascidian. 

 A card describing the specific object shown was placed beside each 

 Microscope, so that no detailed description would be further necessary ; 

 but he miglit mention briefly that the series originated as follows. Two 

 simple Ascidians of the same species were under observation in a small 

 dish ; one was observed to eject a number of ova, and in about one 

 minute the second Ascidian discharged some spermatozoa, and fertilised 

 them : then the process of development proceeded, as illustrated in the 

 specimens exhibited. The specimens had been seen by well-known 

 experts in such matters, and as they had considered them to be an 

 exceedingly complete and valuable series, it had been thought worth 

 while to bring them for exhibition before the Fellows of the Society. 



The President expressed his sense of the indebtedness of the Society 

 to Mr. Watson Baker for his extremely interesting exhibition, and also 

 proposed that their thanks should be voted to Messrs. Watson and Sons 

 for their kindness in lending the Microscopes under which the objects 

 were shown. 



The thanks of the Meeting were unanimously voted to Mr. Watson 

 Baker and to Messrs. Watson and Sons. 



Dr. G. J. Hinde, F.R.S., then read his paper ' On the Structure 

 and Affinities of the Genus Porosplmra,'' which he illustrated by dia- 

 grams, and by the exhibition of numerous specimens, a large number 

 of which he had found in his garden at Croydon, where they had no 

 doubt been weathered out of the Chalk, and were now commingled in 

 the thin layer of surface soil overlying the Chalk. 



The President said it would be unnecessary to ask the Fellows 

 present to return their thanks to Dr. Hinde — as they had done so 

 already— for his very interesting communication, which was in itself 

 an object lesson on the way in which a subject of that kind should be 

 approached. He had worked out the structure of Porosphsera from 

 materials which, though very abundant, did not appear to have been 

 carefully studied by anyone who had hitherto taken it up ; they all 

 seemed to have been satisfied with noticing the mere external appearance. 

 Long before Mr. Worthington Smith took up the subject of Coscino- 

 pora in the Bedford Gravels, Mr. Read brought to Prof. Owen a mass 

 of these beads which he had picked out of the gravel in close proximity 

 to a number of flint implements ; and Mr. Wyatt also found a large 

 number of these specimens, which were still preserved in the geological 

 collection. The President also thought that his own father, Mr. Samuel 

 Woodward, was one of the earliest to notice Coscinopora, as he had 

 figured them in his Geology of Norfolk, as far back as 1833, and might 

 possibly even have antedated Phillips. 



Mr. D. J. Scourfield asked whether it was known what was the 

 special function of the radial canals, and how was the water supposed 

 to circulate in these curious organisms ? 



Dr. Hinde in reply, said that Phillips named these forms in 1829 ; 

 and that Mr. S. Woodward in 1833 adopted Phillips' names for the 

 sirao fossils. He believed the radial canals were excurrent in function ; 



