PLATE XV. 



Planolites. 



Fig. 1. A nodule of chert, with casts of annelid trails or burrows on its surface. 



LAOTIRA CAMBRIA (p. 32). 



Fig. 2. A specimen of the type of fig. 4, with the lobes in strong relief. 



Fig. 3. A specimen of the type of fig. 3 of PI. XIV. All regularity of structure is lost. 



Fig. 4. A distorted specimen, with all the lobes radiating from a common center. 



Fig. 5. A nodule, with a combination of casts of annelid trails or burrows and a narrow-lobed 



medusa. 

 Fig. 6. A nodule with portion of a complex medusa upon it. 



All figures natural size and reproduced from photographs. The outlines of the lobes, etc., 

 were marked with ink before the photographs were made, with the result of giving some 

 i if them too much relief in the figures of this plate and of Pis. XXI and XXII. 



134 



