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peared to exclndo tho opinions of foreign arachnologists who had worked 

 out the subject and had communicated the results. He remembered more 

 particularly a paper by Prof. Claparede in which he described at some 

 length the circulation and the structure of the heart, and illustrated the 

 subject with figures, but the conclusions he came to were not the same as 

 M r. Underbill's. Prof. Claparede, on the contrary, thought there was both a 

 forward and a backward aorta, and that the current divided at the heart, 

 going partly backward and partly forward, though he thought the main 

 current was the backward current. The observations upon which his con- 

 clusions were based were made on very young living spiders. He fancied 

 that there was also a somewhat elaborate paper by Prof. Berkau on the 

 same subject, in which he confirmed, on the whole, the observations of Prof- 

 Claparede, but attributed the sucking action to the action of the trophi. A 

 paper had also appeared by Prof. McLeod, of Louvain, on the sucking 

 action of the Araehnida, in which he had drawn the whole thing with 

 extreme skill, attributing the sucking action to the oesophagus and the 

 sucking stomach. He remembered being considerably interested and pleased 

 with this paper at the time he read it. He was not sure that he quite 

 understood Mr. Underbill's remarks as to the movement of the blood cells 

 in the lungs, but thought he seemed to take the different lamina? to be 

 entirely detached organs. In the same paper to which he had referred Prof. 

 McLeod had described the pillars joining the different gills, and had figured 

 them rather carefully. He remembered that when he saw Mr. Campbell's 

 specimens and sections of spider's lungs, they came to the same conclusion 

 that there was some connection between the laminae, but they could not 

 quite decide whether they were pillars or not— this was prior to the appear- 

 ance of Mr McLeod's paper, though he did not think Mr. Campbell had ever 

 published anything upon the subject. 



Mr. Underhill said that Mr. Lowne had just looked at his specimen and 

 found that the fibrous separating layer of the eye was not present in it. The 

 diagram w r as not taken from the eye of an Epeira, but from some other 

 species, and he had not cut any sections of the eyes of Salticus. As 

 regarded the circulation of the blood, he did not wish to contradict Prof. 

 Claparede, whose paper on the subject he had not seen, but, of course, if he 

 said he had seen it go in both directions, no doubt it did so. It was, how- 

 ever, very difficult to see, and it was possible that a mistake might be made 

 from seeing it apparently moving in both ways, so that anyone looking at it 

 in one direction would see it moving both ways, though there was really only 

 a backward current. The movement of the heart was very clearly seen in 

 spiders, the pulsations going along the heart like waves. As to the valves, 

 he was quite aware of what the text books said about them, but that con- 

 stituted his difficulty, because he could not find them, although he would not 

 say positively that there were none. The salivary glands were situated one 

 in each jaw. The gills were attached at one end, but were free at the other 

 end, and were not quite free at the sides. As for the pillars which the 

 President mentioned having Been, he could not help thinking that some 

 small hairs musi have been mistaken for pillars, or else the sections which 



