HARDWICKE'S SCIENCE-GOSSIP. 



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THE OEMER SHELL AND ITS INHABITANT! 



By W. H. booth. 



ANIFOLD are the amusements 

 open to the wanderer on the sea- 

 shore ; but of all these shell-col- 

 lecting affords us the widest and 

 most pleasing field for study. 

 Only those who have devoted some 

 time to tliis fascinating subject 

 can imagine the infinite variety 

 and multitude of the shells which 

 inhabit our coasts. We lose, how- 

 ever, a great part of the enjoy- 

 ment if we are not acquainted with 

 ^ the forms, shapes, and general habits 

 of the creatures which inhabit those 

 empty valves we see so plentifully 

 strewing the shore. 



With the view of giving some little 

 information on the subject of the Ormer 

 {Haliofls tuherculatd) to the readers of 

 Science-Gossip, I have taken up my pen to 

 describe it to the best of my ability, trusting 

 that this short paper may induce others to con- 

 tribute short monographs on other species. The 

 habitat of this species nearest to us is the island of 

 Guernsey. It occurs pretty plentifully in all the 

 Channel islands, but more especially so in the above- 

 named island. Naturalists are very much divided 

 in opinion as to whether this may be admitted to 

 be a British species or not ; but this point may have 

 been settled by some of our eminent conchologists 

 ere now. I see that it has been allowed a place in 

 the native collection of the British Museum, and at 

 all events it will not do us much harm if we allow 

 it to take up its stand among our own collections 

 of indigenous shells. Premising that the Ormer is 

 a member of the class Gasteropoda, of the great 

 division MoUusca, I will at once proceed to a de- 

 scription of the shell. As may be seen by reference 

 to the illustration, it is rather a flat shell, having a 

 series of apertures or openings in a row near the 

 edge, and following the spiral curve. These aper- 

 tures ai'e very minute on the apex, gradually be- 

 Ko. 103. 



coming larger as they approach the end of the 

 shell. Although termed apertures, only a few (six 

 or more) are open, the others being blocked up by 

 the pearly substance of the interior of the shell. 

 The outside is generally of a dusky hue, and vari- 

 ously coloured with red, brown, and here and there 

 a few patches of green. In some specimens the red 

 becomes somewhat brilliant, and more rarely we 

 have bright green ones. This exterior is rendered 

 rather rough by a large number of small ridges 

 running down from the apex to the base, and about 

 half a dozen transverse bands, which seem to be 

 formed by the various additions to its habitation 

 which the animal makes. That part of the shell 

 which appears at the top of the engraving is ex- 

 ceedingly thick and strong : from this part it gradu- 

 ally gets thinner down to the edge, where it is 

 about the thickness of an ordinary-sized common 

 limpet. Hence its strength is somewhat consider- 

 able ; but several marine animals are fond of boring 

 into the outside, and so disfigure and weaken it- 

 The apex of the whorl is extremely liable to get 

 worn, when it appears shining like the interior, and 

 it is somewhat rare to find a specimen not at all 

 rubbed. Like the Limpets ( Pa^'c'/Zr/), whose near 

 relation the Ormer is, it clings fast to the rocks, 

 but only to those which are covered with the sea at 

 ordinary low tides, tnus being only procurable at 

 spring tides. At first sight it may appear to be 

 very different, and far removed from the Limnet; 

 but further examination shows us a most beautiful 

 gradation between the genera Patella and Hallotis. 

 It may not.be uninteresting to some readers to give 

 some little thought and consideration to this grada- 

 tion, which forms but a small part of that beautiful 

 order and arrangement existing throughout the 

 whole of the Mollusca. The first of our series. 

 Patella, has a well-known and common representa- 

 tive in the common Limpet {Patella vulgata), which 

 we everywhere meet with, clinging fast to the rocks 

 on every portion of the beach, and without any 

 aperture at all in its shell. The second is one very 



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