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46. Jasper found in boulders in a strand of the Upper Coatzacoalcos. 
47. Argillaceous stone in layers, little inclined, resting on the porphyry, No. 9. 
48. Guigosina stone. 
49. Calcareous stone with a circular design, found on the brow of the hills of 
Masahua, in the source of the stream Tolistoco. 
50. Calcareous stone with cavities, resting upon another similar to that on the 
Cerro del Convento. 
51. Variegated marls resting upon sandstone, on a hillock near the Hacienda de 
la Chivela. 
52. Earthy marls, taken from a cavity in the calcareous rock in the ascent to 
the Portillo de la Chivela. 
53. Common marl lying over the sandstone, No 38- 
54. Calcareous breccia on the road from the Venta to San Miguel. 
55. Pearl-stone breccia, found in loose fragments in the stream followed in go¬ 
ing from Zanatepec to the Upper Ostuta. 
56. Lamellar specular iron ore, from the neighbourhood of Tarifa. 
BANKS OF THE RIVER COATZACOALCOS. 
57. Sandstone with a base of ferruginous clay, from above the confluence of the 
river Chimalapilla. 
58. Greenstone rock, from a rapid a little before Angostura. 
59. Metamorphic, or primary limestone, from the bank of the river a little be¬ 
low the mouth of the Malatengo. 
60. Decomposed granite, from the great rapid below the old landing place of 
Mai Paso. 
61. Clay from the small hills on the banks of the river in its lower course: a 
from the hill of Oajaquena ; b from that of Churriagao ; c from that of 
Penas Blancas. 
62. Clay in layers, alternating with others of sand at Juchitan, 12 metres below 
the alluvial soil which covers the plain. 
63. Calc tuff, from the margin of the fountain of Agua Caliente. 
HILLS NEAR THE LAGOONS AND ISLANDS IN THE UPPER LAGOON. 
64. Grey-wacke, very finely grained, of the island of Iguana or Mitiacix. 
65. Porphyry with basis of jasper, from the Mitiacxocuen. 
66. Porphyry with basis of argillaceous stone, from the summit of the hillock of 
Potrero. 
67. Trachitic porphyry with small veins of calcedony, from Danigu. 
68. Conglomerate of argillaceous base, from the small ravine of Chico Zapote 
or Endedchina, near to Danigu. 
69. Jasper, from the small heights near those of the Potrero. 
70. Dioritic porphyry, of the Manguixtiac. 
71. Porphyry from the summit of Umalalang. 
72. Syenitic greenstone from the island of Monapostiac, in large separate 
pieces. 
73. Stratified greenstone, from Natartiac or Cerro Prieto. 
