SCIENTIFIC SUMMARY. 
95 
With one or two exceptions, all the species will be fully illustrated in five 
lithographic plates in the authors’ forthcomirg memoir: in addition to 
which there will be two wood-cut plates of diagram-figures, explaining the 
various parts briefly noticed on the present occasion, and another showing 
the relationship of Lingula to the family. — Geological Magazine, October. 
The Geology of Biluchistan. — Mr. W. T. Blandford contributes a paper to 
Kecords of the Geological Survey of India,” part II., May 1872, which is 
of particular interest as being upon an unexplored territory. His observa- 
tions relate to the geological formations seen along the coast of Biluchistan, 
(commonly called Makran), and those of Persia from Karachi to the head of 
the Persian Gulf, with observations on some of the Gulf Islands. Three 
distinct systems of rock are exposed in these localities, in descending order : 
— 1. Littoral concrete (sub-recent) ; 2. Makran group (post-Nummulitic) ; 
3. Hormuz salt formation (of unknown age). The island of Hormuz is a 
most singular place. It is almost destitute of vegetation, and consists of a 
mass of low craggy hills, brilliantly coloured. Beds of volcanic origin, 
dolerites and trachytes, rock-salt, shales and sandy-beds, are found inter- 
stratified, all belonging apparently to the same series. The rocks are much 
disturbed ; beds of salt and volcanic bands alike dip at high angles. There 
is no evidence to determine the age of these salt-beds ; but they are clearly 
older than the Makran group, for in the Island of Hanjam they crop out 
here and there beneath this group, which rests uncomfortably upon them. 
The Geology of the London Basin is dealt with very ably by Mr. W. 
Whitaker in the “ Memoirs of the Geological Survey.” In the area explained 
by him the formations exposed are the Bagshot Beds, London clay. Lower 
London Tertiaries and chalk. Their general nature is first noticed, and 
then their range, lithological character, and sections are described in detail. 
One chapter is devoted to the sands of doubtful age on the chalk, originally 
classed with the crag by Mr. Prestwick, and subsequently referred to the 
Eocene period by Mr. Whitaker and others. The concluding chapters are 
devoted to Disturbances, with a notice of the likelihood of there being an 
underground ridge of older rocks along the valley of the Thames ; to Denu- 
dations, and to Economics and Springs. In the Appendix there are accounts 
of 488 well-borings, arranged according to counties. To these Mr. Whit- 
aker has added many remarks of his own in regard to the classification of 
the beds passed through j and, together with accounts of 36 borings, they 
form a most valuable record of facts. Other appendices contain copious 
lists of fossils, minerals, &c. The whole work — embracing as it does a 
minute account of the Chalk and Eocene Tertiaries of the London Basin — 
is in the highest degree creditable to Mr. Whitaker. 
The Physics of Geology, — Professor Le Conte, in ^^Silliman’s American 
Journal ” for November, thus concludes a paper which is to be continued : 
“I think, therefore, I am justified in asserting that the phenomena of 'plica- 
tion and of slaty cleavage demonstrate a crushing together horizontally, and an 
up-swelling of the 'whole 'mass of sediments ; and that slaty cleavage demon- 
strates in addition that the up-swelling produced hy this cause alone is sufficient 
to account for the elevation of the greatest mountain chains i*' 
The genus Bhynoholus or the genus Oholellina, 'which is it to he f — Professor 
Hall writes to “ Silliman’s Journal ” for August, asserting that he was first 
