NO. 1 HARTMAN : POLYCHAETOUS ANNELIDS 77 



podia have 3 pale acicula, the posterior ones often have only 2 each. Setae 

 of the first parapodia include hooded, articulate, tridentate hooks (pi. 4, 

 fig. 83) present through the first 3 pairs of parapodia, numbering 6 or 7 

 in a fascicle. By the fourth parapodium they are partly replaced by 

 simple, acute setae, and the hooded hooks come to be transitory such that 

 the distal hook is reduced and the other 2 teeth come to be progressively 

 stouter (pi. 4, fig. 79). From the seventh to fourteenth setiger these 

 heavy hooks are simple (pi. 4, fig. 84) and thereafter are entirely re- 

 placed by simple, limbate setae. Composite spinigers (pi. 4, fig. 85) are 

 present from the fifth parapodium, in the inferiormost part of the fas- 

 cicle ; they number 2 or 3 in a bundle, and are usually accompanied by 2 

 similar, though simple, setae. They continue for a short distance but are 

 absent w^ith the appearance of subacicular hooks. The latter (pi. 4, fig. 

 80) are present at about the tvv^entieth segment. 



Branchiae are comparatively inconspicuous ; the occurrence of the 

 first pair is variable. In collection 767-38 they are first present on the 

 fourth setiger on one side and from the fifth on the other; in another 

 (coll. 1245-41) they are first present from the seventh, eighth, and ninth 

 setigers; among 3 specimens (coll. 1288-41) they are first found on the 

 ninth, tenth, and eleventh setigers; and in still another lot (coll. 1274- 

 41 ) their first appearance is on the twelfth setiger. The variability thus 

 extends from the fourth to twelfth setiger on individuals taken at ran- 

 dom. The number of filaments usually does not exceed 3 or 4 where best 

 developed. Branchiae are continued through a long median region but 

 are absent from a longer or shorter posterior end. Ventral cirri of the 

 first 7 segments are cirriform, thereafter they are padlike. 



The proboscidial armature is delicate; its maxillae are translucent. 

 Mandibles have a long, black streak distally and long, slender basal ends 

 (pi. 4, fig. 76). The maxillae are broad ; the carriers are basally rounded ; 

 the forceps are broadly falcate, thin. The formula on the left side is as 

 follows: maxilla II has 9 teeth, the distalmost tooth widely separated 

 from the second last, maxilla III has 8 teeth, maxilla IV has 7 teeth, 

 and maxilla V has a single tooth. On the right side the formula is as 

 follows: maxilla II has 7 teeth, maxilla III has 10 teeth, and maxilla V 

 has a single tooth (pi. 4, fig. 78). 



The tube is long, slender, and stiiT, covered over with finer and 

 coarser, flat or somewhat rounded fragments over a tough parchmentlike 

 base ; it is closely appressed to the body wall of the occupant, so that the 

 individual is removed with difficulty. It has almost the stiffness and con- 

 sistency of some phoronid tubes and in some instances is quite as long. 



