306 



EEPOET 1892. 



Mr. Gamble obtained Polyzoa from several of the pits opened in the 

 Chatham district, but these were generally found in very restricted 

 horizons. I have sectional sketches of five of these pits, all of which I 

 have since visited, and in one (see annexed sketch) the strata appear to be 

 horizontal, being cut along the strike. Very high up or towards the top the 

 stratum is marked by two iron-stained bands. Just below the highest 



Section slwwing Pohjzoa Zone, Cliatliam Chalh. 





Section A, on tlie south side of Chatham, about 70 feet higli. 1. Upper iron-stained band 

 referred to in the text. 2. Lower iron-stained band. 8. Polvzoa zone. In this section 

 very tew of the dei droid species were found. 4. A bed of Ananchytes and Spatangm 

 conipleteh- invested by Serpula, Menibranipora, Probofcina. and Stomatopora, &c. f). 

 bhowmg the horizontal beddinsj. At * many good Ventriculites were found in the zone ■ 

 indicated. G. Showing dip north-west. (Contributed, with information and examples of 

 the species indicated, by Mr. Gamble.) 



band the Polyzoa zone begins, but the life-climax — if I may be allowed 

 the term— is reached just above and just below the lowest band. In the 

 section now under description this position is indicated by the figure 4, 

 which, Mr, Gamble says, consists of a bed of Ananchytes and Spatangus 

 completely invested by Membranipora3, Serpula;, and adherent forms of 

 Cyclostomata, such as Stomatopora, Proboscina, Diastopora, and other 

 forms. When searching in other pits for Polyzoa, it was found that the 



