222 Miscellaneous. 



5. The Scorpionidte represent a form more ancient than the 

 Araneidce. 



6. The Tetrapneumouous Araneidse present more ancient forms 

 than the Dipneumona. 



7. The appendages of the Pycnogonidoe may be compared with 

 those of the Arachnida, and the Pycnogonida} resemble the Spiders 

 in the structure of tlieir generative and digestive organs. — Annccles 

 des Sciences Naturelles, Zoolojie, ser. vi. tome xvii. 



Oh the Physiology of a Oreen Planarian (Convoluta iSchultzii). 

 By M. A, Baeth£lemy. 



Convoluta ScJiultzii is a singular animal, of a nature to excite the 

 interest of those naturalists who pay attention to the function of 

 chlorophyll. It is not oue of those creatures of doubtful position 

 and, so to speak, intermediate between the two kingdoms, but a 

 comparatively high organism, in which the association with chloro- 

 phyll elements has produced interesting physiological peculiarities. 

 By the extreme kindness of il. Lacaze-Duthiers I have been enabled 

 to study this interesting creature, which lives and develops in 

 abundance at Roscoff. Its anatomy, and especially its embryogeny, 

 must be the subject of a special investigation ; I shall content my- 

 self in this note with speaking of its physiology. 



I shall only state that this Convoluta presents a ciliated cuticle, a 

 muscular layer giving origin to longitudinal bands, and a central 

 parenchyma replacing the digestive tube. There is neither mouth 

 nor oesophagus, and still less an anus. This construction resembles 

 that of the Infusoria, especially of Opalina. 



As regards the chlorophyll element, it is represented by cells with 

 greenish-yellow contents, and presenting a nucleus which is brought 

 into view by attacking the chlorophyll with ether and then treating 

 with potash. These elements are free upon the surface of the cen- 

 tral parenchyma, and when the latter escapes, in consequence of au 

 accidental rupture, it is not uncommon to see one of these cells also 

 escape surrounded by protoplasm. It seemed to me that these 

 chlorophyll-cells multiplied by division of the nucleus. 



I must not forget to mention the existence (which, however, is 

 not constant) of fusiform bacilli inserted into the cuticle by a sort 

 of nail-head, and often collected, to the number of four, at the 

 posterior part of the animal ; and, lastly, of bundles of very fine, 

 granular, parasitic Nematodes, much attenuated at the extremity, 

 which live and move for some time when detached from the animal; 

 but I do not know whether it is to these that we must refer the 

 nematocysts with protractile filaments that Graff has described in 

 Stenostoiaum Sieboldii. 



When held between the fingers, the animal diffuses a phosphorous 



