THE TUATARA.

Hokitika Guardian, 21 July 1923, Page 4

THE TUATARA.

REMARKABLE AN C' KST RY. STRANGE STRUCTURE AND RELATIONSHIP. SCION OF A ONCE NOBLE FAMILY. Australia does not. hold a monopoly in "living fossils." Although she is proud to have the pearly Trigonia shell, a relic of Juras-ie lime*, as well tithe little mar-upiai Antealer (Myrnierihiii- reminiscent of the English Puri lock marsupials of an age long pa-!, New Zealand can also boast of a remarkable reptile, the Tuatara or Sphet'.odoii. declares K. Chapman, A.L.S.. palaeontologist to iho National Museum, Melbourne, in tin article in the "Argil-.” 'Two of these interesting creatures have now been added l the Melbourne Zoo. r i hougil called a beaked lizard, a crocodile might lay equal claim to the title ot lizard, tor it is so peculiar in ii- .structure that it has keen pku-od in a separate order, which includes many ie.-sil ropiv.-oiitn-lives. Without desiring to offend this interesting little "beastlie,” we may truthfully say t hat ii is a lot.ol v scion of a mice noble family, whose ancestry runs back not merely to a thousand year- or -o, Imt on a moderate estimate in, perhaps 50,00!), 1)111). Although one oi the nio-t primitive of reptiles, it is generally regarded hv naturalists representing the ancestral stock from which the higher reptiles, and later, (he mammals, were derived. 8o that it- I 100 I i- very blue, indeed. The Tuatara. in give it the .Maori Maine, is now found only on some small islands oif the liort beast coast o| New Zealand. It is eerl.'iin, however. that at one tie;., ii inhabited th. mainland, for its hones lei.'r been

loum! in the middens along wit Ii those oi the Moa birds. Dinorni-, and Noinrnis. Since it- is one of the most interesting of living animals mi t lie fine of the globe, it i< sat isfnetory to le.trn tliiii Ihe New Zealand Government I is 1 bleed it under snecinl protection. In fa t, lial it not been immediately protected, the inroad- o! civl isi lion in the i'll 111 of tlll-ll file , d..e-, al|d ». .It -. am! et mi the Maoris, woo uv loud ul ii lor iood, the titalar.i would have speedily gone the way of the Dodo and 1 .end b n tor's pa riot . Livin'*; a.- it dee.- in a burrow, ibis Would lend In protect ii to some extern, lint even i hat does nm ensure immunity. It -Imres it- burrow with vari.'ii, kinds el' p.-tre.l-, though oilier Inatiras are not allowed entry. It is sail that the t nut ara lives on the right side the burrow, anil the petrel on tie. I"!t. When ,l,i- agreement w:iilrnvtl Mil no one can say. The eggwhich are laid by ihe imp am are hair!" ; J In ihe son. Tim iimul.ation oe.'ii'i'.'s a period ot 1:1 months, so licit diiiiu'f a part of i lie time this proi 'stliui lie arresli.l by cold. Tiialtrat'i" miner lazy in their movements., am! -i.iwlv dr.i i heinsidves along Hi" ground unless i xriied about limit' fool, wl:ltdi they will only take alive, in tlm shape ot small animals. The tuatara, or, seient ifii ally, the sphi'in don pniirtuiiis In. .-piiiled Weil;.:-! not lit. belongs to the other

rliyneli'teephalia. a d.imlua'ii grout) of root i!i" in Permian, Ti'ia-sie, and Jtir as-ir linim-: Inti ala-, i- now the Miliary r tnnining spi r es. They nr • lizard like in shape, and in some pointhave similar struct lire a- in ilm hooklik" urir'css mi the ribs, seen built ill h’/.?rd- and lards; Ibese uneinaie appendages are not, however, found in the In.-- il examples of the order. The nostrils are double, the lower jaws co tnectecl by cartilage, and the vetebral holms deeply concave hoi It hack and front. The pdale lias a single row of feel It. separated by a fissure from the row on the edge of the upper jaw. The

tcetJi of the lower jaw fit in this‘l groove. They are not'," as is usual with teeth, implanted, in sockets, but (irmly welded to the edge of the jaw. The front of the jaw is beak-liko, lienee the name, and the premaxilla carries a pair of ehisel-shaptjd teeth. On the top of the skull is a vacuity, the parietal foramen, and beneath is a functionless eye or parietal gland. This rudimentary eye is seen through the skin in the young tuatara, but the skin thickens over as it grows older. What is known as the pineal body is t! structure seen in fishes and reptiles, as <i process of the brain that perforates the aof of the skull. Jil sharks it ends below the skin in a closed vesicle. Young frogs show it above tita surface :il the skull, hut- it uud egoes degeneration later in life. Dt* Graf first discovered this body as an eye-like organ in the British slowvainii (Angitis), and Sir Baldwin Spencer confirmed it in the present genus Sphenodun, as having distinct traces of a retina. Some authorities regard the jj i i ion 1 body as a primitive structure representing an upturned median eye, like the conning tower of a submarine. Others, however, look upon the eyelike structure as a secondary modification. Professor Howes and Dr TL •Swinnerton, who also worked upon the B’phencdon in regard to the skeleton, found that- Hie vertebrae passed through a paired cartilaginous stage, and iu its later details most resembled those of the lower baltachians (group of the frogs and toads). It, is dear that the “beaked lizards” descended from a stock which also stive rise to the frogs and toads of the

earlier ages. This is seen by the embyrulngieal and other researches made on I - 1 ; ii the latter and Sphenodun. On looking over the relics of the past, a way liack for a! least 59 million yeart. in the Carboniferous period, we find the e'riiest back-boned animals wlvrb exhibit lingered limbs. These are gri’i'.t jiirin'iibians known Lo paiaeoiil.o-logii-ts as Stcguccphalians, wlm-e battened ehaninms were formed of a root of sirong bone, apparently made to re

-is l hard knocks, Yery soon afterwards, probably within the next httlfiiiiliimi years, in the Permian, arose another group of digitated, back--I,oved animals, which, being more or I:--- i dated, are placed with the reptiles. This is the group in which our ii, ~ • Sphenodun belongs, comprised in Hie order Rhynohiuephnlia, or “beak-head-.” In llie copiier slates of German and in tie I’erniain magne-ian limestone of Durham, in England, are found some of these earliest "beak-heads." Titus. Proterosaurus had a body about IJl't long. Another curious animal he hinging to this group is the Hyperudapedoti, (lescrihed from some slightly younger beds at Elgin, in Scotland, bv Pi niessor Huxley. It had a short, flat U'lm.l. triangular head, and the upp"r jaws and palatines were furnished vAih several rows of llatioued cmical i !■".i.-hing teeth like enamelled bui-iou-i, with a single row oil tin* lower jaw diiis prohnblv indicates that it was I'iikl of dining upon shellfish. The fa mi I v to which the living SpheJiotlnn I cl. lie- include- several interesting am I'st i:■ 1 form-, some large ami othersmall. The gem of the bcaked-liz tr.i family was undoubtedly I loniocusanI'lis, which was wry like Sphenodun, lint generally smaller, and in some species measuring only about Silt in length. It diU'eri'il. however, from tli" living form in not having the !>• klike or uneinaie processes on the ribs. This little civ; mi re mils! have been very common near the coast in Upper lura-.-ii' times, when that pecnliai mml deposit was' forming in the Oolitic.- ,-ea- ol Euroive, and which now i.tin* remarkable lithographic stone. Into the niudbank of this Jurassic shcrehTio were washed till kinds ol Hot sain, -itch as dragon-flies and small animals from the land a- well as cut t Ir-fishes and other marine objects from the sea. I'",*:-"limit easts ol fossil bonked ID. .•'■i. fc-'ii tie- Foul Ii African Karoo an t the ()ol it c of France and Bavaria arc lo lie seen in tin* v all-cases of the gtl!Tv of lo- ii- in the National Mu.-e tun. Tim nio-t remarkable thing about th - rnup of tlie Rliy n> hocoohnliaiis ii' ;<[ no rein. (ins have been found in eisv turni ition bet ween tlie Juras-ie ■ I i(.. -iib-rcccnt. so that we can almost -ay that we possess a living “beaked lizard”- "through the interv q'■ a ul Providence."