PTERODACTYLK. 



PTEROPODA. 



The Mun author point* out that the three first fingers of the 

 PUrodaetyle agree in itructure with those of the fore foot of living 

 Lizards; but a* the hauJ of the frail reptile was to be converted 

 into an organ of flight, the joiuU of the fourth or fifth finger were 

 lengthened to become expanaon of a membranous wing. Thus, in 

 P. tosytrettrM, he observes, the fourth finger is stated by Cuvier to 

 have four elongated joints, and the fifth or unguent joint to be 

 omitted, as iU preeence is unnecessary. In the P. erauirottrit, 

 aooording to Qoldfuas, this claw is present upon the fourth finger, 

 which thus has fire bones, and the fifth finger is elongated to carry 

 the wing. Throughout all these arrangements in the fore foot the 

 normal numbers of the type of Lizards are maintained. " If," con- 

 tinues Dr. Buckland, "as appears from the specimen engraved by 

 Uoldfiua of P. crcunrottrii, the fifth finger was elongated to expand 

 the wing, we should infer, from th* normal number of joints in the 

 fifth finger of Lixards being only three, that this wing-finger had but 

 three joints. In the fossil itself the two first joints only are pre- 

 set-red, so that his conjectural addition of a fourth joint to the fifth 

 finger in the restored figure, seems inconsistent with the analogies 

 that pervade the structure of this and of every other species of 

 Pterodactyle, as described by Cuvier. According to Qoldfuss, this 

 species; had one more toe than Cuvier assigns to the other species ; in 

 this respect it is so far from violating the analogies we are considering, 

 that it adds another approximation to the character of the living 

 Lizards." After referring to the difference manifested in P. crcuri- 

 rottrit from the other Pterodactyles, in having the fifth instead of the 

 fourth finger elongated, as above noticed, for the purpose of expanding 

 the wing, Dr. Buckland states that it is however probable that the 

 fifth toe had only three joints, for the same reasons that are assigned 

 respecting the number of joints in the fifth finger ; and he observes 

 that in P. longirottrit, Cuvier considers the small bone in the foot to 

 be a rudimentary form of a fifth toe. 



The Pterodactyles have been found in the lithographic limestone of 

 the Jura formation at Aichstiidt and Solenhofen, which abounds with 

 remains of Fish, and of Brachyurous and Macrurous Crustaceans, 

 and where Xiphotari (Limuliu) not (infrequently occur. The fish 

 examined by Cuvier belonged, partially at least, to marine genera. 

 Ue distinguished, for example, a well-characterised species of anchovy, 

 probably Cl*pea ipratliformit (Blainv.). Libelluliv and other insects 

 have also been found in this Solenhofen shite. The other localities 

 are Lyme Regis (Lias), Bantz, and Stonesfield (Ooolite). 



Cuvier, speaking of the Solenhofen district, observes that there is 

 no doubt that^at the time of the deposit of the lithographic slate, 

 there lived in that canton crocodiles, Limuli, and other beings whose 

 geographical distribution is now confined to the torrid zone, together 

 with these flying Saurians, which flitted about by means of the mem- 

 brane sustained by a single finger, suspended themselves and perhaps 

 crept by the aid of the other three fingers, stood upon their hind legs 

 only, and had their enormous gape armed with small pointed teeth, fit 

 only for seizing insects and small animals. 



Dr. Buckland thinks it probable that the Pterodactyle had the 

 power of swimming so common in reptiles, and now possessed by the 

 Vampire Bat of the Island of Bouin. (' Bridge-water Treatise.') 

 " Thus," says the Professor, " like Hilton's fiend, all qualified for all 

 services and all elements, the creature was a fit companion for the 

 kindred reptiles that swarmed in the seas or crawled on the shores of 

 a turbulent planet : 



11 ' The Fiend 



O'er bog, or itctp, through unit, rough, dcnw, or rare, 

 With bud, hnd, wing!, or feet, pursues bis war, 

 And iwinu, or ink, or wadn, or rrcept, or flic*. 1 



With flocks of such-like creatures flying in the air, and shoals of no 

 less monstrous /cAMjroMurt and PUiiotanri swarming in the ocean, and 

 gigantic crocodiles and tortoises crawling on the shores of the primeval 

 lakes and riven air, sea, and land, must have been strangely tenanted 

 in these early periods of our infant world." ('CJeol. Trans.,' new 

 series, lit, part i.) 



In the ' Bridgewatcr Treatise,' we find the size and form of the foot, 

 and also of the leg and thigh, adduced as showing that the Ptero- 

 dactyles had the power of standing firmly on the ground, where, with 

 their wings folded, they possibly moved after the manner of birds ; 

 and an opinion that they could also perch on trees, and climb on 

 rocks and cliffs, with their hind and fore feet conjointly, like bats and 

 lizards. 



Cuvier, as we have seen, conjectured that the food of these flying 

 Saurians consisted of insects and other small animals, and be thought 

 that, from the magnitude of their eyes, they may have been also 

 noctivagona. Dr. Buckland refers to the preeence of Urge fossil 

 jMettufar, or Dragon- Kile*, together with many other insects, in the 

 seme quarried with the Soleuhofen Pterodactyles, and to the occur- 

 rence of the wings of Coleopterous Insects, mingled with the bones of 

 those Saurians in the oolitic slate at Stonesfield, as proof that large 

 Joes oh existed at the same time with them, and that they may have 

 contributed to their supply of food. He adds however that the head 

 and Usth of two species of Pterodactyls are so much greater and 

 stronger than is necessary for the capture of insects, that the larger 

 species of them may poembly hare fed on fished, darting upon the 

 Utter from the air, after the manner of Sea-Swallows, or Terms and 



Solan Geese. The enormous size and strength of P. crauirottrit, ho 

 observes, would not only have enabled it to catch fish, but also to kill 

 and devour the few small Marsupial Mammalia which then existed 

 upon the land. 



A new species has lately been discovered by Mr. Bowerbank iu the 

 Kentish Chalk, which seems to have been more colossal than any 

 hitherto described. Some portions of the upper maxilU prove thu 

 total length of the head to have been upwards of 16 inches; and the 

 bones of the upper extremity indicate a width of from 16 to 18 fcot 

 from the extreme point of one wing to the other. 



PTEUODICTYUM. [POLTI-IKEKA.] 



PTEROOLOSSUa [lUiiriiARiDJB.] 



PTEKULO'BIUM, a small genus of Plants belonging to the natural 

 order JUyamlnoia, so named from its pod ending in a membranous 

 wing. The genus was first mentioned by Mr. Brown, in the api>endix 

 to Salt's ' Travels in Abyssinia,' and from a species, P. Kantuffa, 

 which is also named by Bruce, and described by him as being ordered 

 to be cut away from the roods when the king was going to travel. 

 The genus is found in India as well as in Africa, and even the Kanluffa 

 occurs there, as it U the Catalpinia, laceraiu of Roxburgh, but 

 referred to Mimota by De Candolle, and called M. Kcmtuffa; having 

 been ascertained to be identical with the Indian plant, and belonging 

 to this genus, it has been called P. laceram. The genus contains 

 only a few species of trees and climbing shrubs covered with strong 

 sharp hooked prickles. 



PTE'ROMYS. [SCII-BID.K.] 



PTEROPHY'LLUM, a genus of Fossil Cycadeous Plants from the 

 Oolite of Yorkshire and beds of the same age in Scania. (Bronguiari) 



PTEROPLEURA. [QECKOTID&] 



PTEROPODA, a class of Molliuca placed between the Oaiteropoda 

 and lirachiopoda by some writers, and by others next the Cephalopoda. 

 The number of species is not Urge. They pass their entire life in 

 the open sea away from shelter, except that which is afforded by the 

 gulf-weed. In appearance and habits they resemble the fry of the 

 other forms of Molluica, They are supplied with a pair of fli]>|>errt 

 or wings (hence their name), by means of which they pass r.ipidly 

 through the water. They swarm in tropical and arctic seas, and are 

 sometimes so numerous as to colour the ocean for leagues. They ore 

 the principal food in high latitudes of the species of whale and of 

 sea-birds. They are rarely found on the sea-shore, and only one or 

 two species have been accidentally taken in the British seas. 



" In structure, the Plcropoda are most nearly related to the marine 

 univalves, but much inferior to them. Their nervous ganglia are 

 concentrated into a mass below the oesophagus ; they have auditory 

 vesicles, containing otolites ; and are sensible of light and heat and 

 probably of odours, although at most they possess very imperfect 

 eyes and tentacles. The true foot is small or obsolete ; iu Cteodora 

 it U combined with the fins, but in Clio it is sufficiently distinct, and 

 consists of two elements; in Spiralit the posterior portion of the 

 foot supports an operculum. The fins are developed from the sides 

 of the mouth or neck, an ! are the equivalents of the side-lappet* 

 (Ejii i>odia) of the sea-snails. The mouth of Pneumodermon is furnished 

 with two tentacles supporting miniature suckers ; these organs have 

 been compared with the dorsal arms of the cuttle-fishes, but it is 

 doubtful whether their nature is the same. A more certain point of 

 resemblance is the ventral flexure of the alimentary canal, wlii. h 

 terminates on the under surface, near the right side of the neck. The 

 pteropods have a muscular gizzard, armed with gastric teeth ; a liver. 

 a pyloric ccocum, and a contractile renal organ opening into the cavity 

 of the mantle. The heart consists of on auricle and a ventricle, and 

 is essentially opistho-branchUte, although Ametimes affected by thu 

 general flexure of the body. The venous system is extremely incom- 

 plete. The respiratory organ, which is little more than a ciliated 

 surface, is either situated at the extremity of the body and unpro- 

 tected by a mantle, or included in a branchial chamber with an 

 opening in front. The shell, when present, is symmetrical, glassy, 

 and translucent, consisting of a dorsal and a ventral plate united, with 

 an anterior opening for the head, lateral slits for long filiform pro- 

 cesses of the mantle, and terminated behind in one or three points ; 

 in other cases it U conical, or spirally coiled and closed by a spiral 

 operculum. The sexes ore united, and the orifices situated on tho 

 right side of the neck. According to Vogt, the embryo Pteropod hax 

 deciduous vela, like the sea-snails, before the proper locomotive 

 organs are developed. (Huxley.) 



" From this it would appear that while the Pleropoda present some 

 analogical resemblances to the Cephalopoda, and permanently represent 

 the larval stage of the sea-snails, they are developed on a type 

 sufficiently peculiar to entitle them to rank as a distinct group ; not 

 indeed of equal value with the Oaitenpoda, but with one of its orders. 



" This group, the lowest of the univalve or encephalous orders, 

 makes no approach towards the bivalves or acephaU,' (Woodward, 

 'Treatise on Shells.') 



De BUinville divides this group into two section;, Thccotomatu and 

 Qymnotomata ; 



A. Thecotomata. Animal furnished with an external shell ; head 

 indistinct ; foot and tentacles rudimentary, combined with the 

 fins ; mouth situated iu a cavity formed by the union of the 



