EOBEETS — UPPER SILURIAN CORALS. 61 



simple line-sliaped calices. These are all of small size. So, too, are 

 the species of tlie next gemis Monticuliioora, i.e. "little monntain pore," 

 from its siii'face being varied by tlie elevation of tuberosities. All 

 the species of this genus are branching, save one — If. pajjillata, 

 whose corallum is thin and incrustating. If. Fletclieri has circular 

 calices regular in size ; while those of M. jpulcliella are oval, or rarely- 

 hexagonal, but differ in size, those occupying the tuberosities being 

 larger than those that come up in the low-lands. Three other 

 : species are met with, but rarely. 



Next in order is Lahecheia conferta, a disc-like coral, which is 

 widely distinct from every other polyparian production ; for the 

 calices that come up abundantly to its surface are tubercles in- 

 stead of cups, from their margins folding in upon the centre, and, 

 as a matter of course, their septa are as rudimentary as are those 

 of the Favosltidce. 



Hahjsites catemdaria is another aristocratic coral that does not per- 

 mit others to claim affinity. This is the common "chain-coral," named 

 so by universal consent, from its cahces forming a series- of inter- 

 linked loops across the upper surface, like the links of a golden chain. 

 This is a pet species of palaeontologists, for M. Milne Edwards has 

 recorded no less than twenty-six synonyms for it eii vogue at different 

 times and places. It is abundant in every quarry of Wenlock shale, 

 but the finest specimens come from Benthall Edge. 



Now for the parasitical corals, Syringojpora hifurcata, S.fascimlaris, 

 md S. serpens — three species not easy to disting-uish at certain stages 

 Df their growth. They lived upon well-to-do shells and corals in 

 jhose ancient seas, just as species with like habits do now, throwing 

 ip here and there a short calicinal tube as they crept over their sur- 

 faces. In after life gemmation out of these produced a mass of 

 straight slender coralhtes, which had an independent existence, and 

 p^ew tall and comely. 



Two others, and the history of our common Wenlock corals is 

 !nded. Thecia Stvindernana is a massive, but rather thin coral, 

 laving a flat upper surface covered with beautiful star-like calices, 

 v^hose elegance of design is owing to the development of their septa. 

 Che other species, T. Grayana is like it in form, but differs in having 

 )ut twelve septa instead of sixteen or eighteen. 



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