Dec. 14, 1888.] 



SCIENTIFIC NEWS. 



605 



were none of the parasites found in July, but in October 

 they were abundant. They occasion large abscesses, 

 which kill the fish by exhaustion. 



Swarm of Libellula Quadrimaculata. — According 

 to the Entomologist's Monthly Magazine, a migratory 

 swarm of this insect appeared off the Essex coast last 

 summer. Mr. R. McLachlan, F.R.S., mentions that such 

 swarms are not uncommon on the Continent, but are un- 

 exampled in this country. 



The Fallow Deer. — There are two varieties of the 

 Fallow Deer {Cervus dura) common in parks in this 

 country, namely, the spotted and the black. Until 

 recently it has always been supposed that the dark 

 variety was introduced into England from Norway by 

 James I. in 1602, on account of its superior hardness of 

 constitution ; but Mr. J. E. Harting now proves, in his 

 excellent work entitled " Essays on Sport and Natural 

 History," that a dark race of Fallow Deer existed in this 

 country at least two centuries earlier than the date above 

 given. This deer is a native of Southern Europe and 

 North Africa, but the date of its introduction into this 

 country is uncertain. It was probably never indigenous 

 in any part of the British Isles in historic times. 



The Rabbit Pest in Australia. — According to the 

 Queenslander, Pasteur's remedy for this scourge is still 

 doubtful. The rabbits which had eaten vegetables 

 sprinkled with a culture of chicken-cholera died, but the 

 disease did not spread to other rabbits in the same 

 enclosure. Dr. Bancroft has studied the coccidium 

 parasite, which lodges in the liver and is a common 

 affection in rabbits, and he thinks that there would be 

 neither difficulty nor danger in infecting rabbit colonies 

 with this parasite. 



Bird-work v. Child-work. — In England we often see 

 rooks, starlings, and, in coast localities, gulls following 

 the plough and picking up the grubs or maggots which 

 the ploughshare turns up. In France, where such birds 

 have mostly been shot down, we see the same task per- 

 formed by children who have to follow the plough, each 

 provided with a little jar for the reception of the vers 

 blancs, the larvae of the destructive cockchafer. It need 

 scarcely be said that the work is done less perfectly and 

 at greater cost than if it had been committed to the birds. 

 Besides, the children ought to be at school, or at play. 



Comparative -Development of the Sense of Smell. — 

 Recent experiments have shown that on the average the 

 sense of smell is more acute in men than in women, and 

 that they consequently can detect and recognise smaller 

 quantities of odoriferous substances. If we compare the 

 olfactory organs of male and female insects, we find that 

 in a majority of cases those of the males are the more 

 highly developed, so that a sexual difference in this 

 sense may be traced very widely in the animal kingdom. 



Fauna of Fernando de Noronha. — Mr. J. C. Braune 

 discusses, in the American Naturalist, the peculiar fauna 

 of these islands and the probable means of its introduc- 

 tion. The chief mammalian species present are rats and 

 mice, which are numerous to a degree probably un- 

 equalled. There are no serpents, but there is found an 

 Amphisbcena, which the Brazilians call the two-headed 

 snake. There is also a lizard which has sometimes a 



forked tail. The tail of this species is long and brittle, 

 and if a broken portion does not fall off, the fracture 

 may heal over so as to hold it securely, whilst by its 

 side a new tail sprouts from the injured part. 



Respective Power of Vision in the Eyes. — In a 

 number of persons whose keennesses of eyesight was 

 tested in the Anthropometric Laboratory in Manchester, 

 the right eye was found to have the advantage over the 

 left. 



The Pigment of Blood as a Means of Distinguish- 

 ing the Interchange of Gases in Plants in the Light 

 and in Darkness. — The production of free oxygen can 

 be shown by means of hasmoglobine, which is converted 

 into oxyhasmoglobine, and shows the two well-known 

 absorption bands. If a straight thread of Spirogyra, placed 

 in the colouring-matter of venous blood, is illuminated 

 with a spectrum, there is formed a bright red zone of 

 oxyhasmoglobine, which begins in the extreme red, rises 

 as far as C, and declines from there to the green, where 

 it disappears. 



Survival of the American Bison. — ItJ r is interesting 

 to learn that, according to Professor R. T. Hill, of the 

 University of Texas, two herds of the American bison 

 (commonly miscalled buffalo) still exist in Texas. The 

 proprietors of the ranches are, according to our contem- 

 porary Science, doing much for their protection. 



THE TEETH OF WHALES. 



Part II. 

 (")F those cetaceans which possess teeth in the strict 

 sense of the word wehave an admirable example 

 in the cachalot, or spermaceti whale, a creature which 

 feeds upon many of the .larger fish, and no doubt finds 

 its dental armature of considerable service in holding 

 its active and slippery prey. 



In this whale the^teeth are principally situated in the 

 lower jaw, and fit, when the mouth is closed, into 

 conical cavities provided for them in the upper. They 

 are large, strong, and massive, of fine quality as far as 

 their actual substance^is concerned, but not of any great 

 hardness. So, at least, it would seem from the fact 

 that in an adult whale they are always more or less 

 blunted, while in an old animal|the points are completely 

 worn away. Their number is very variable. A spermaceti 

 whale may have more than fifty teeth, or it may have 

 less than forty, this variation being due to individual 

 idiosyncrasy, and not to accidental loss. But the aver- 

 age number would seem to be forty-two, .of which 

 sixteen are situated in the upper jaw. 



These latter, however, are very easily overlooked, 

 for they project so little from the gum (scarcely more 

 than half an inch) that only by a careful search are 

 they likely to be detected at all. Nor do they seem of 

 any great importance, for they are so slightly attached 

 to the jaw-bone that, when the skull is being prepared, 

 they almost invariably come away together with the 

 gum in which they are imbedded. 



By the natives of the South Sea Islands the teeth of 

 this whale are, or were, held in the highest veneration, 

 and considered as much too precious to be owned by any 

 private individual. And more than once has one tribe 

 actually gone to war with another in order to secure one 



