104 On Iodide of Silver and its Alloys. [June 15, 



The third lung-bearing segment is supplied by the ganglion which lies 

 in that segment. The fourth lung-bearing segment has no ganglion 

 lying in it, and appears to depend entirely for its nerve-supply on the 

 median nerve given off by the ganglion which, as in Androctonus, is 

 placed in the next following segment. 



These relations can only be understood by the aid of drawings. 

 The woodcut shows diagrammatically in three figures, fig. 2 the dis- 

 position in Androctonus funestus (agreeing essentially with Newport's 

 description), fig. 3 the disposition in Scorpio cyaneus of Ceylon, fig. 4 

 the disposition described by Dufour. This last diagram has been 

 constructed from Dufour's drawing. It is without doubt erroneous in 

 important particulars relative to the large ganglion of the prosoma, 

 and is very probably erroneous in regard to other particulars. 



It is worthy of attention as tending to associate the European 

 scorpions of the sub-genus Euscorpius with those of the type of Butlms 

 afer, to which Sc. cyaneus of Ceylon belongs, that in Scorpio Italicus 

 and Scorpio Carpathicus, I have found the same disposition of the 

 ganglia and of the primary branches of the ventral nerve-cord as that 

 drawn in fig. 3. The only difference observed was that the ganglia 

 in these European species are all a little further forward, so as to lie 

 close to the anterior limit of the segments in which they occur. 



We thus find that an important anatomical difference obtains 

 between the Scorpions with triangular sternum (Androctoni) and the 

 Scorpions with pentagonal sternum (Euscorpii, Buthi, &c). Whether 

 the Scorpions with band-like sternum (Telegoni) differ from or agree 

 with either of these types in respect of their nervous system, has yet 

 to be discovered. 



VII. " On the Specific Heat and Heat of Transformation of the 

 Iodide of Silver, Agl, and of the Alloys Cu 2 I 2 .AgT. 

 Cn 2 I 2 .2AgI, Cu 2 I 2 .3AgI,Cn 2 I 2 .4AgI, Cu 2 I 2 .12AgI, PbI 2 .AgL" 

 By Professor M. Bellati and Dr. R. Komanese, Professors 

 in the University of Padua. Communicated by Professor 

 A. W. Williamson, For. Sec. R.S. Received June 7, 1882. 



(Abstract.) 



The authors' calorimetric investigation refers to substances which 

 have been already studied by Mr. G. F. Rodwell (" Proc. Roy. Soc." 

 vol. 32) as to their expansion and contraction by heat. 



After having detailed the method of experimenting and tabulated 

 the results of determinations for each substance, the authors recapitu- 

 late the results in the following table : — 



