July 1, 1869.] 



HARDWICKE'S SCIENCE-GOSSIP. 



145 



LAMPEETS AND LAMPEENS. 



By MAJOR HOLLAND, R.M.L.I. 



HE queries respect- 

 ing these members 

 of the family Petro- 

 myzonidcc which 

 have appeared in 

 the pages of this 

 publication, have 

 induced me to at- 

 tempt to put to- 

 gether in a readable shape 

 sundry odds and ends of notes 

 concerning them collected 

 from all possible sources and 

 interwoven with the reminis- 

 cences of my own personal 

 investigations made during a 

 residence of nearly three years 

 in Gloucester. While rum- 

 maging over the bibliography 

 of these creatures to see what 

 others had said about them, so 

 many contradictions presented 

 themselves, that it became evi- 

 dent that toprocure a supply 

 of them, and to study them in the flesh, with the aid 

 of the scalpel, the syringe, and the microscope, was 

 the only way to set one's mind at rest. A series of 

 fresh specimens were obtained from the waters of 

 "the blue Sabrina," and the appliances of the 

 museum of the Royal Hospital, Haslar, brought 

 into play to throw light upon their dark points. 

 The readiness with which both Lampreys and Lam. 

 perns can be got, and their very remarkable struc- 

 ture, render them attractive and instructive subjects 

 for the amateur, while the position which the order 

 Cyclostomata occupies, as one of the connecting links 

 between two great divisions of the animal kingdom, 

 has ever made them objects of the highest interest 

 to comparative anatomists and men of science. 



"Erom whatever form or race of animals the 

 zoologist advances towards the next succeeding it 

 No. 55. 



in the scale of nature, he will find himself insensibly 

 led on by such gentle gradations that the transition 

 from any one class to another is almost impercepti- 

 ble. Nihil per saltum is one of the most obvious of 

 the laws of creation." 



In the cephalopods, the most highly organized 

 members of the Fourth Division {Mollusca), we have 

 the first appearance of an osseous system. The 

 well-known "cuttlebone," or sepiostaire, common on 

 every sea beach, and the gladius of the Calamary 

 Loligo are but rudimentary shells, mere dermal 

 secretions analogous to the shield-plates we find 

 imbedded in the mantle of the slug ; it is in the 

 cranial cartilage and fin-plates of the Cuttlefish, 

 Sepia officinalis, that we get the first traces of a 

 true internal skeleton. On the threshold of the 

 Eifth Division [Vertebrata) stands the Lancelot, 

 Amphioxus lanceolatus, a little creature scarce 

 two inches in length, the most anomalous and extra- 

 ordinary of all living things, " a vertebrated animal 

 without a brain, a fish with the respiratory system 

 of a mollusk, and the circulatory system almost of 

 an annelid." One step higher, eyeless, and with 

 only the merest apology for fins, yet one of the most 

 murderous and terrible of all parasites, stands the 

 Hag-fish, or Borer, Myxine glutiuosa, the lowest 

 of the order Cyclostomata (circle-mouthed) to which 

 our friends the Lampreys and Lamperns, Petromy- 

 zonidce (stone-suckers), belong. In the latter, the 

 cranium exhibits a soft cartilaginous texture, while 

 the spine consists of a still softer cartilaginous stem, 

 which passes along the entire length of the body; but 

 the only indications of distinct vertebrae exist in the 

 presence of slight and almost imperceptible rings of 

 osseous substance and delicate intervertebral mark- 

 ings distinguishable upon the surface of the stem, 

 and in vertical section (as at h, fig. 115). 



A thin section of the Chorda dorsalis (fig. Ill) 

 shows it to consist of large polygonal cells ; some 

 parts of the chorda, especially those near the 

 centre, are soft and pulpy : in these the cells can be 



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