Geology. 351 



xv, figs. 2a, 3). Because of the abnormal and very irregular 

 lamellar" thickenings of the posterior region of the shell margin 

 (no two shells are alike in this character) covering over the scar 

 of attachment, Noetling thinks these animals finally lost fixation 

 and lay with the dorsal shell on the sea bottom. 



He arrives at this conclusion because the majority of the speci- 

 mens by far are ventral shells; some show the inner side of the 

 dorsal valve and but a few preserve both valves in place. One 

 might suppose that if the animal finally came to live as suggested 

 by the author, all the specimens would preserve both valves, 

 because after death, as the animal matter decayed, its place 

 would be occupied by the "very soft calcareous mud" in which 

 it lay. The reviewer thinks that during the weathering process 

 the very thin dorsal shell is either dissolved away, or because of 

 its deeply cleft nature and exterior papillose condition it adheres 

 firmly to the outer rock, only to be dissolved away by weather- 

 ing from this side. The fact that the mantle is constantly 

 depositing shell on the outer posterior cardinal area is evidence 

 that in some way it embraced foreign objects by which it held 

 the shell in place. In old age such deposition may cease, but as 

 these animals apparently lived in large communities they are 

 nevertheless firmly held in place by their neighbors. On the 

 other hand, if lying with the dorsal valve down in the soft 

 mud, as suggested by the writer, it would seem that death must 

 soon ensue through suffocation, because of the mud squeezing in 

 through all of the many lateral clefts of the dorsal valve, but 

 especially in preventing free water circulation with a fresh 

 supply of food and oxygen. 



Of the many cemented brachiopods, it is very rare to find one 

 preserving the object of attachment, and on this account it 

 should not be expected to occur here more than elsewhere. The 

 reviewer believes that these animals lived with the deeply cleft 

 dorsal valve uppermost, or that the posterior region of both valves 

 lay somewhat embedded in the mud, with the greater portion of 

 the anterior region protruding above the sea floor. 



The author correctly removes these shells from the Thecidiidse 

 and regards them as more closely related to the Prpductidae. He 

 adds, "it may be that this aberrant group can even be included in 

 this family so rich in forms" (p. 147). It seems now more proba- 

 ble that the Leptodiclse (new name) arose in some cemented form 

 of the Productidse, in which case it would be best looked for 

 among iStrophalosia. c. s. 



III. Miscellaneous Scientific Intelligence. 



1. Les Prix Nobel en 1903. Stockholm, 1906 (P. A. Norstedt 

 &, Soner). — The recipients of the Nobel prizes in 1903 were as 

 follows : Henri Antoine Becquerel for his discovery of spon- 

 taneous radio-activity ; Pierre and Marie Sklodovska Curie for 

 their researches in the phenomena of radiation discovered by H. 

 Becquerel ; Svante August Arrhenius for the theory of electro- 



