212 bulletin: museum of compaeative zoology. 



Liais, Emm. L'espace celeste ou description de I'univers accompagnee 

 de rt'cits de voyages entrepris pour en completer I'etude. Paris. 

 2me edition. (1881.) (First edition, 1865.) 



This work contains the only sketches published, so far as I can learn, 

 of the stone reefs immediately south of Cape Santo Agostinho (p. 545, 

 546). Of the stone reef in general it is said that it is higher than high 

 tide at but few points. It is a foliated sandstone of quartz and feldspar 

 with fragments of shells hardened by a silico-calcareous cement. He 

 notes that the reef is not one unbroken wall, but is made up of a number 

 of straight parallel lines, never curving. " The rock of the reef bears evi- 

 dence of displacement since its formation. Its beds dip seawards at an 

 angle of about forty degrees. At some places the dip is not so much, 

 but at others it is more marked, and south of the Serrambi point I have 

 even seen a part of the reef standing on edge." He is of the opinion that 

 these sands were deposited in the sea in horizontal beds and subsequently 

 displaced by crust movement. He speaks of the protection of the ex- 

 terior by polyps. He evidently adheres to an earlier opinion about the 

 direction of the reef, for he says (p. 544), that " this question is . . . 

 connected with one of the most remarkable facts in the history of our 

 planet, namely, the alignment of the surface wrinkles upon the arcs of a 

 great circle extending over immense distances." 



The Pernambuco reef is said to bear N. 20° E., and to be parallel to 

 the direction of the western Alps (p. 548). The reef rocks are considered 

 to be of later age than the hills of the coast (p. 547), and not far 

 removed from the modern epoch. He does not think the rock is now 

 forming (p. 548). 



This writer was stationed at Olinda for eight months (1859-60) as 

 an astronomer of the Imperial Observatory, and his observations are 

 based upon personal observations (p. 279). 



Liais, Emm. Inclinaison des couches de roches arenac^es modernes 

 des cotes du Bresil ; extrait d'une lettre a M. Elie de Beaumont. 

 Compt. Rend. 1860, L. 762-3. 



This letter is dated Olinda, March 8, 1860. The author says, "The 

 rock of the reef that borders the coast of America is a quartzose sand- 

 stone filled with shell fragments ; " that its structure is grossly schistoid, 

 and the beds inclined at an angle of 35° to 40°, with the strike N. 

 20° E. 



The reef is made up of fragments of straight parallel lines, but not 

 always lying in the same prolongation, " and as the coast is modelled on 



