[Fig. 3]. Spores of Lecidea enteroleuca to illustrate the simple, hyaline type. X 760.
[Fig. 4]. Spores of Biatorina chalybeia to illustrate the 2-celled, hyaline type. X 760.
[Fig. 5]. Spores of Bilimbia trachona to illustrate the several-celled, hyaline, fusiform or dactyloid type. X 760.
[Fig. 6]. Spores of Bacidia fuscorubella to illustrate the several-celled, hyaline, acicular type. X 760.
[Fig. 7]. Spores of Bacidia umbrina to illustrate the several-celled, hyaline, hamate or spirally twisted type. X 760.
[Fig. 8]. Spores of Rhizocarpon alboatrum to illustrate the several-celled to many-celled and muriform, hyaline to brown type. X 760.
[Fig. 9]. Spores of Rhizocarpon petraeum of the same type as those shown in the last figure, but larger, and usually composed of more cells. X 760.
[Fig. 10]. A vertical section through an apothecium of Lecidea rupestris: a, the hymenium, composed of asci and paraphyses; b, the hypothecium; c, the mycelium, the cells of the algal host, and particles of the limestone on which the plant was growing; d, the weak, light-colored, covered exciple. X 79.
[Fig. 11]. A vertical section through an apothecium of Buellia parasema, the thallus below, and a portion of the woody substratum: a, the hymenium, composed of asci and paraphyses; b, the strongly developed, dark colored exciple; c, the dark colored hypothecium; d, the thallus, composed of interwoven hyphae, and enclosing cells of the algal host, a portion of the woody substratum. X 79.
[Fig. 12]. One branched and one unbranched paraphysis of Buellia parasema. X 450.