Royal Society of Edinburgh. 313 



2. On the Agrarian Law of Lycurgus, and one of Mr Grote's 

 Canons of Historical Criticism. By Professor Blackie. 



3. On the Occurrence of Amoebiform Protoplasm and the 

 Emission of Pseudopodia in the Hydroida. By Professor 

 Allman. 



The author described the contents of the small tubular appen- 

 dages, named Nematophores by Busk, which are developed upon 

 certain definite points of the bydrosome in the Plumularidce. 

 These contents were shown to consist of a granular protoplasm, 

 with occasionally a cluster of large thread-cells embedded in it. 



The protoplasm has the property of emitting pseudopodia, which 

 are very extensile and mutable in shape, and exactly resemble the 

 pseudopodial prolongations, whose occurrence among the Bhizopoda 

 is so eminently characteristic of this group of Protozoa. The con- 

 tents of the nematophores, indeed, except alone in the presence 

 of thread-cells, are indistinguishable in structure, and in the phe- 

 nomena presented by them from the sarcode or protoplasm, which 

 forms the substance of an amoeba, a difflugia, or an arcella. 



Monday, 18t7i January 1864. — His Grace the Duke of 

 AKGYLL, President, in the Chair. 



The following Communications were read : — 



1. Description of the Lithoscope, an instrument for dis- 

 tinguishing Precious Stones and other bodies. By Sir 

 David Brewster, K.H. 



The Instrument was exhibited. 



2. On the Temperature of certain Hot Springs in the Py- 

 renees. By E. E. Scoresby-Jackson, M.D., F.R.C.P. 



In the year 1835, Principal Forbes very carefully observed the 

 temperatures of certain springs in the Pyrenees, with the view 

 of ascertaining to what extent changes of temperature occur in 

 them. Observations previously made were, for several reasons, of 

 uncertain worth, and Principal Forbes was desirous of then fixing 

 " data for future observers with a degree of accuracy hitherto un- 

 attempted." 



The author having determined to spend his autumn holidays in 

 the Pyrenees, believed that a careful repetition of such observa- 

 tions, after the lapse of twenty- eight years, would afford results of 

 some interest. He furnished himself with accurate thermometers 



