EARLY DEVONIC HISTORY OF NEW YORK AND EASTERN NORTH AMERICA 223 



extreme variation. Thus in figure 14 we have a four pronged grapnel 

 surmountino: the hook with the other end of the rod bearing^ the combination 

 just mentioned. There are also double hooks, on the neck of which acces- 

 sory branches are developed not as prongs but as arms at different dis- 

 tances from the axial apex. These are shown in figures 2, 12, wherein the 

 branched upper end of the spicule is preserved. The tendency to add 

 accessory branches to the neck and shaft seems to result in such comblike 

 forms suggestive of conodont teeth as are presented in figures 16, 19, 

 wherein there is a loss of the symmetrical development shown in the 

 simpler spicules. 



In figure 1 1 is represented a slender and very deeply divided two pronged 

 grapnel, with a rather different type of hook. This specimen is shown for 

 its whole length and there is no indication of the other axes except that 

 on the shaft and I am not sure that this structure should be thus regarded. 

 At all events the upper end of the rhabd is simple and smooth. 



A different type again is presented in figure 13 where the shaft is 

 curved and the prongs of the hook are wide apart and curved outward like 

 the horns of an ox. This is an occasional form seen only in the example 

 presented. There is a series of forms, consisting of straight slender rhabds 

 bearing a trifid hook at one end but no indication of any modification at 

 the other. One of these is of very delicate shape, the terete shaft bearing 

 deeply and narrowly recurved prongs which bend first in and then outward 

 at the top. This pattern of anchorate spicule is shown in figure 10. The 

 usual type, however, is stouter, the prongs shorter, less bent and recurved 

 and these may be either smooth, [figure 9,] or may bear irregularly scattered 

 barbs [fig. 3, 15]. In all these no indication is given of the remnants of the 

 other triaxial arras. Occasionally one finds a dumb-bell shaped spicule with 

 flattened ends which may be regarded as of similar nature as the monaxile 

 diaspid [fig. 26]. 



To the form of the sponge bodies of which these spicules are the com- 

 ponents we can have only a feeble clue. That they were regularly reticu- 

 lated species with abundant prostalia is indicated by the extensive masses 

 of broken smooth rods.- Possibly the root prostalia are represented in 

 part by the anchorate spicules but this is not at all a necessary inference 

 from the presence of the latter for we have shown in our treatise on the 

 Paleozoic Dictyosponges that such spicules are frequent in the vertical 

 spicular bundles of certain species (Physospongia, Cleodictya). The 

 umbels so characteristic of Carbonic dictyosponges seem to be quite absent 

 here and indeed in most every respect of spicular form these Gaspe bodies 

 seem to differ from what we have been led to regard as features of the 

 Dictyospongidae. 



Girty has described' from the New Scotland beds of the Helderbergian 



'N. Y. State Geol. 14th An. Rep't. 1895. p. 269, pi. i, 2. 



