A HISTORY OF WORCESTERSHIRE 



Here, too, are met with several small representatives of those remarkable 

 Palaeozoic crustaceans known as trilobites, which take their name from 

 the circumstance that the body, or middle portion of the carapace, is 

 more or less distinctly divided into three longitudinal lobes. Externally 

 trilobites present a distant resemblance to woodlice, but they were 

 marine creatures related to the existing king-crabs of the Moluccas. 

 They are very important to the palaeontologist, as their occurrence always 

 indicates that he has to do with Palaeozoic rocks. The trilobites from 

 the Malvern shales belong to the genera Olenus, Conocoryphe, Sphcer- 

 ophthalmus, and Agnostus. In some of the shales the small Olenus humilis 

 occurs in such profusion as to have suggested the name of ' Olenus 

 shales ' for these particular beds. The green shales overlying the black 

 shales in the neighbourhood of Hayes Copse contain a curious net-like 

 fossil named Dictyonema socialis. This presents a considerable superficial 

 resemblance to the modern lace-corals, but since its skeleton is not 

 calcareous, and bears cups for the reception of polyps, it is considered 

 to belong to the same group as the recent sertularians, or hydroid 

 polyps. 



The invertebrate Silurian fossils of Worcestershire, although much 

 more numerous in species than those of the Cambrian (and in certain 

 localities exceedingly abundant in individuals), require somewhat less 

 detailed notice than those of the last-named period for the reason that they 

 are for the most part identical with those of the neighbouring counties. 

 A large series of these fossils were collected by the late Dr. Grindrod, 

 of Malvern, which are now in the Museum at Oxford, and there is also 

 a fine collection in the Museum of the Malvern Field Club. 



Like those of other counties, the Silurian rocks of Worcestershire 

 are characterized by the abundance of brachiopods, or lamp-shells, and 

 cephalopods, or chambered molluscs ; gastropods, or ordinary univalve 

 molluscs, and bivalves^ being much less abundant. In the May Hill Sand- 

 stone (Upper Llandovery), which takes its title from the hill of that name 

 in Gloucestershire, two very characteristic fossils are Fentremites oblongus 

 and P. lens^ both easily recognizable by having vertical partitions within 

 the valves ; they often occur in the form of casts. Other brachiopods 

 from this formation are Atrypa reticularis, Orthis protensa, 0. calU- 

 gramma, Strophomena compressa, S. antiquata, and Stricklandinia. Of these 

 Atrypa and Stricklandinia are the most common. The two species of 

 Pentamerus and Orthis calligramma occur in the May Hill Sandstone 

 of the Lickey Hills, near Bromsgrove. Gastropods are represented 

 by the nautilus-like Bellerophon and the spiral Murchisonia ; while 

 the cephalopods include the long, straight Orthoceras barrandei and the 

 less common Tretoceras bisiphonatum. Among tube-dwelling worms 

 we have "Tentaculites ornatus and Cornulites serpularia. Trilobites, too, 

 are abundant, but none are peculiar to this particular formation, such 

 forms as Calymene blumenbachi and Phacops stokesi having a large vertical 



* Strictly speaking, lamp-shells are also bivalves, but in these the two valves are front and 

 back, instead of right and left. 



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