摘要:

The remains of a large camelid from the Upper Pleistocene (Carolinian) tar‐seep deposits near Talara, Peru, aro deseribed with measurements. Comparison with other described South American Pleistocene Camelidae indicates its conspecific identity withPulaeolama aepuatorialisHoffstetter, 1952. The absence of interlophar styles on both upper and lower molars is considered the main basis for tho recognition of a now subgenus,Astylolamasubgen. nov.Palaenlamuais considered, therefore, to possess three subgenera,Palaeolama. (Palaeolama),P. (Protauchenia) andP. (Astylolama.) A single large left phalanx II from the same deposit is assigned toPalaeolamasp., but may belong withinPalaeolama crassaHoffstetter, 1952 which is known only from a single metatarsal recovered from the Rio Chiche. An isolated right lower caniniform tooth resembling C1ofP. weddelliiand P1ofTanupolama stevensiis reporte

ISSN:0370-2774    

DOI:10.1111/j.1469-7998.1965.tb02014.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

An investigation is made of the homology of the nasal apparatus of the Dipnoi, in order to determine whether the posterior naris is homologous with the choana of tetrapods or with the posterior external naris of fishes. The ontogeny of the nasal capsule ofProtopterusis described in detail. The nervous and venous systems of tho snout region ofProtopterusare also duscrbed. It is found that whereas the pattern of the nervous and vascular systems is very similar in all Dipnoi, the structuro of the nasal capsule in theLepidosiren‐Protopterusstock differs greatly from that of theNeoceratodusstock. the homology of the various components of the depnoan nasal coasule is revised and it is shown that there are no evidences of a direct relationship of the Dipnoi with the tetrapods. It is further concluded that the posterior naris of Dipnoi is homologous with the posterior external naris of fishe

ISSN:0370-2774    

DOI:10.1111/j.1469-7998.1965.tb02015.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

The officiency of euro (Macropus robustus Gould) and marloo (Meguleia rufu Desmarest) reproduction was investigated on two pastoral leases, Mount Edgar and Mundabullangana, froni 1959 to 1961. Despite fluctuations in physical condition (due to seasonal changes in food availability and temperature), females of both species breod continuously and exhibit high lcvels of fertility and fecundity throughout tho year. The incidence of quioscent blast‐ ocysts has been documented in three populations of these kangaroos. A hypothesis is suggested that the ecological role of the quiescent blastocyst is to extend the sequence of parturitions under drought conditions. Three moasures of male fertility (test8is weight, density of sperm and total numbers of sperm in the ejaculato) showed no significant seasonal changes. Both species woro shown to have very much lower densities of sperm in the semen than any domestic eutherians. Female euros were aged by a dental index, and it was found that old females had a reduced fertility. The old malos of both species showed a reduced fertility. Continuous breeding and high reproductive efficiency in euros and marloos allows for a large recruitmcnt in these species. These phenomena seem to be related to the relatively long period of time between conception and weaning of tho young and the uncertainty of prediction of t'he optimal weaning season in an irregular desert environmen

ISSN:0370-2774    

DOI:10.1111/j.1469-7998.1965.tb02016.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

This study is based on 2,194 specimens ofHolochilus sciureus berbicensisfrom the coastal region of British Guiana. The rodents live in the grassy savannahs where population density in circumscribed areas is often high and they easily colonize the cultivated areas where their normal reproductive pattern, assisted by migration in wet weather, results in them periodically attaining plague proportions. Both males and females become sexually mature at a relatively early age and continue to breed throughout their lifetime, in addition producing young at all times of the year. There is some evidence to indicate that there may be precocious sexual maturity at times of heavy rainfall. It would seem that predation of one sort or another is high in this region and this may be compensated to some extent by a fairly high reproduction rate.

ISSN:0370-2774    

DOI:10.1111/j.1469-7998.1965.tb02017.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

New crustaceans parasitie on African freshwater fishes of the Nile, or former Nile, and Niger systems are described. The taxonomy of a group of closely related species ofArgulusis clarified, and errors in the older literature are corrected. Additional information on distribution is presented.

ISSN:0370-2774    

DOI:10.1111/j.1469-7998.1965.tb02018.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

Some details are given of the biology of two species of lizard:Agama cyanogaster(Rüppell) (Agamidae) andMabuya striata strikta(Peters) (Scincidae). They occupy different niches in the same habitat and their biology differs considerably.Agamais oviparous, laying its eggs in the rainy season so that they hatch before it becomes too dry.Mabuyais ovoviviparous with the young being born mainly in the first half of the dry season. In both species tho variety of diet was wide, but ants were most commonly eaten byAgamaand beetles byMabuya

ISSN:0370-2774    

DOI:10.1111/j.1469-7998.1965.tb02019.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY