Correspondence — G. C. Crick. 47 



The lower division of the White-leaved Oak Shales may represent 

 the Swedish zone with Beyrichia Angelini, and perhaps the Festiniog 

 Beds of North Wales. It is, however, more probable that it 

 represents the uppermost portion of the Paradoxidian. The greater 

 part of these shales, however, belongs to the zone of Sphcerophthalmus 

 alatus ; but it is possible that other zones, both immediately above 

 and immediately below, may be represented in the district. The 

 middle part of the Bronsil Shales has yielded Asaphids and Olenids 

 in association with Dictyonema, and may be correlated with the 

 Tremadoc beds which yield the Mdoma-Niobe fauna. The author 

 prefers to endorse the Continental view of these rocks, and to 

 group the Tremadoc Series with the Ordovician, with the reservation 

 that the Dictyonema-shales of Europe should be regarded as belonging 

 to the Tremadoc, the base-line of the Ordovician being drawn 

 immediately below these shales. 



The paper contains an account of the Hyolithidse and trilobites 

 of these rocks. Three new species of Hyoliihus are named and 

 described in full, and four in outline, while a revision of Holl's 

 species K. fistula is given. Notes are also given, by Mr. Philip 

 Lake and the author, on Agnostus trisectus. Gheirurus Frederici, and 

 other trilobites, and a name is given to certain cylindrical bodies 

 which appear to be the eggs or excreta of some animal. 



In the Appendix on the Cambrian Brachiopoda of the Malvern 

 Hills, after making a few brief remarks as to our present knowledge 

 of these fossils, Mr. C. A. Matley proceeds to describe a new species 

 of Obolella and a new variety of Acrotreta Sahrince. Species of 

 Lingulella, Lingula, and Acrotreta are described, and a revision is 

 given of Obolella (?) Salteri, Lingulella Nicholsoni, Acrotreta Sabrince, 

 Zinnarssonia Belli, and Kutorgina cingulata vars. FMlUpsi and pusilla. 



cozE^iiESiPOisrnDZEi^aiE:. 



ADDITIONAL NoItE ON AMMONITES CALCAR, ZIETEN. 



Sir, — Since writing the note on Ammonites calcar, Zieten, that 

 appeared in the Geological Magazine for December, 1899 (pp. 554- 

 658), there has been found belonging to the specimen there described 

 another original label, which it seems desirable to record. This 

 was fastened in the Museum register ; not on the page where 

 the specimen was entered, but some two leaves from the place, so 

 that it was discovered quite by accident. Fortunately, when the 

 specimen was registered the register number was written on the 

 label, so that there can be no doubt whatever about the label 

 belonging to this actual specimen. The label bears the following 

 inscription in the handwriting of Dr. Bruckraann, from whom the 

 fossil was obtained : " Ammonites calcar Benz ; Zieten. Brown 

 Jura ^ ; Ornatenthon. Uuic \_sic'] of Zieten's collection ; extremely 

 rare ! Gamelshausen in Wiirttemberg. Professor Dr. Kurr told me 

 that he was about to buy the whole of Zieten's collection, only in 



