133 
toes (iii & iv), and one sesamoid behind the last joint of the same 
toes. 
In most artificially-prepared skeletons of Ruminants, more or less 
of the small bones, often regarded as accessory, are lost ; but they are 
really for the most part beautifully indicative of traces of adherence 
to the archetype, and I have on that account particularized them in 
this notice of the anatomy of the Aurochs. 
Measurements of the Trunk of the Aurochs. 
Inches. 
Length of vertebral column from the atlas to the sixth caudal 
vertebra, measured across the diapophyses .......... 81 
Length of vertebral column over the neural spines ...... 88 
Length of cervical region over the diapophyses.......... 17 
Length of dorsal region RD 2D IY AATEC. BSL 30 
Length of lumbar region ditto .................0.0. 13 
Length of sacral and six caudal ditto ................ 21 
Depth of spine of seventh cervical ..............-.4-- 8 
Depth of spine of first, second and third dorsal, being the 
three longest, each ...... Sgt pare yale, aie yeto wislirts)s =, wiajanenete 11 
Mpenc es fico ribet. So 210. 2, SP. US SIMI Es 9 
Length of ninth, or the longest .................. vee 18S 
Seven ribs articulate by separate hemapophyses to the sternum. 
Length of diapophysis of fourth lumbar, or the longest .. 44 
Breadth of atlas across the neural arch ................ 7 
Extreme breadth across the spines of the ilia  .......... 14 
Extreme breadth across the pubis, from the inner edge of 
each acetabulum ...... cate wees EE LOOM PRR 
2. Description oF A NEW Genus or AcEPHALous Moutvsca, oF 
THE FAMILY PECTINACEA, COLLECTED By Cart. Sir Epwarp 
BELCHER DURING THE voyaGE or H.M.S. Samarane. By 
Artuur Apams AND Lovett Reeve, FF.L.S. 
(Mollusca, pl. 1. fig. 2.) 
[Enlarged to twice its natural diameter.) _ 
Genus HEMIPECTEN. 
Hemirecten Forzesranus. Hem. testd orbiculari, Anomieformi, 
tenuissimd, hyalind, concentriceé lineatd, linearum interstitiis eximie 
reticulatis ; valud inferiore planulatd, postic? auriculatd, auriculd 
longitudinaliter radiatd, sinu infra profundo, margine opposito 
subtiliter denticulato; valvd superiore converd, extus interdum 
decussatim rugosd, vix auriculatd; cardine edentulo, ligamento 
angusto, marginali, cartilagine parvo solido in cavitatem centralem 
superficiariam valvis ambabus ligamentum intersecante ; pellucido- 
albd, valud superiore interdum rufo-aurantio radiatd. 
Hab. Sooloo Archipelago, Eastern Seas. 
The subject of the foregoing description, which constitutes an ex- 
tremely interesting discovery in the acephalous family Pectinacea, is 
an inequivalve shell, partaking of the characters of Pecten and Ano- 
