Zoological Society. 



208 



excepting even the Camelidce. It is only during the earlier period of 

 intra-uterine life that the corpuscle of mammals has a nucleus corre- 

 sponding to the permanent one in the corpuscle of lower animals. In 

 birds, the nucleus, when exposed by a weak acid, is commonly longer 

 in proportion to its breadth than the envelope ; but there are some 

 exceptions, and the nucleus becomes globular or nearly so when in 

 contact with water. In the blood-corpuscle of mammals the central 

 spot, so often mistaken for a nucleus, is not visible in the best focus 

 and light ; then if the object-glass be so slightly removed from the 

 corpuscles as not to destroy their clear contour, a dark spot appears 

 in their centre ; if the glass be next so far moved towards the corpus- 

 cles as to place them slightly within the focus, the dark spot will be- 

 come bright ; and when altogether invisible in a bright light, the spot 

 may be instantly brought into view simply by diminishing the light. 



Note. — The following measurements are all in vulgar fractions of 

 an English inch ; but for the sake of convenience, the numerator is 

 omitted throughout, as it is invariably 1, and the denominators only 

 are printed. The measurements of the blood-discs are given as they 

 lie fiat, unless when a T indicates a measurement of their thickness . 

 By L.D. the long diameter and by S.D. the short diameter is de- 

 noted. The measurements refer exclusively to average sizes. The 

 nuclei were measured after exposing them by the action of dilute 

 acetic acid on the envelopes. 



MAMMALIA. 



Homo 3200 



T... 1 12400 



SiMiJE Catarrhini. 



Simla Troglodytes 



Pithecus Satyrus 



Hylobates Hoolock 



leucogenys 



Rafflesii 



Semnopithecus Maurus 

 Cercopithecus Mona .. 



sabaeus 



fuliginosus 



ruber 



pileatus ...-. 



pygery thrus 



— Petaurista 



— griseo-viridis 



— iEthiops 



Macacus radiatus 



— Rhesus 



— niger 



— cynomolgus 



— Silenus 



— nemestrinus 



— sylvanus 



— melanotus 



Cynocephalus Anubis . 



— leucophseus 



SiMi^ Platyrrhini. 

 Ateles subpentadactylus .... 



3412 

 3383 

 3368 

 3425 

 3539 

 3515 

 3468 

 3342 

 3530 

 3395 

 3578 

 3401 

 3478 

 3429 

 3454 

 3563 

 3429 

 3583 

 3429 

 3430 

 3493 

 3338 



Ateles ater 



— Belzebuth .. 

 Cebus Apella 



— capucinus ., 

 Callithrix sciiireus 

 Jacchus vulgaris .. 

 Midas Rosalia 



Lemuridjs. 



Lemur albrfrons . 

 -Catta 



— Anjuanensis 



— nigrifrons . 

 Loris tardigradus . 



— gracilis .... 



Cheiroptera. 



Vespertlllo murlnus 



noctula ...... 



Piplstrellus ... 



Plecotus auritus ... 



3461 

 3555 



3620 



Insectivora. 



Talpa Europaea .... 

 Erinaceus Europaeus 

 Sorex tetragonurus . 



Plantigrada. 



Meles vulgaris . . . 

 Arctouyx collaris 



3602 

 3589 

 3467 

 3454 

 3713 

 3624 

 3510 



3976 



4003 

 4440 

 3691 

 3461 



4175 

 4404 

 4324 

 4465 



4747 

 4085 

 4571 



3940 

 3609 



