460 AUTOLYTUS BRACHYCEPHALUS. 
is barrel-shaped, and has forty-four rows of violet points. The colour is light orange, and 
the tips of the tentacles are orange. The anterior and posterior bristles are figured in Plate 
CXXXV, fig. 15a and 15d. 
De St. Joseph met with an example of 20 mm. in length in which the sexual elements 
covered the dorsal vessel and fell mto the ccelom; and another of seventy-two segments 
in which the head of a female bud with four eyes appeared at the fourteenth segment, yet 
it had no ova, no swimming-bristles, and no modification of the intestine. A third example, 
a nurse-stock of thirteen segments, had a female stolon of fifty-eight segments with the 
head well developed, the body filled with eggs from the third segment to within twenty of the 
tail. Its swimming-bristles were developing. From the fourteenth segment of other examples 
a male bud depended, with or without natatory bristles and altered or unaltered intestine, 
according to the development of the spermatozoa. In the sexual buds there were many 
red points on the ventral surface, and the segmental organs were developing. The French 
author is inclined to think with Langerhans that the A. macrophthalmus and A. luxurians 
of Marenzeller refer to the same form. 
Southern also considers A. luxurians, Marenzeller, synonymous with this species, 
the only difference being that A. luxurians has small reddish-brown eyes, whereas in this 
the eyes are large and red. 
AUTOLYTUS BRACHYCEPHALUS, Marenzeller, 1874. Plate CXXXV, fig. 16--head and 
anterior region. 
Specific Characters—Head with four large eyes, and occasionally additional specks, 
like Marenzeller’s examples; palpi fused dorsally. Tentacular cirri and cirri of second 
segment longer than the following; conspicuous epaulettes behind head. Pharynx with 
thirty marginal papillae, and the organ is reddish-violet. Body bluish-red, forty to sixty 
segments. Double row of pigment-grains on dorsal surface of each segment, long bar 
in front, shorter behind. Alternation in length of dorsal cirri. Two anal cirri. In the 
Irish examples there were thirty denticulations to proboscis—four much larger than rest— 
six smaller occurring between the larger. 
Habitat. —Blacksod and Clew Bays, dredged (Southern). Abroad, Adriatic 
(Marenzeller), Madeira (Langerhans). 
SYNONYMS. 
1874. Procerea brachycephala, Marenzeller. Sitzb. K. Akad. Wiss. Wien, p. 460, Taf. vi, fig. 2, and 
Taf. vii, fig. 2. 
1879. 3 ms Langerhans. Zeitschr. f. wiss. Zool., Bd. xxxu, p. 580, Taf. xxxi, 
fio. 12. 
1914. Autolytus - Southern. Proc. Roy. Ivish Acad., vol. xxxi, No. 47, p. 41, pl. v, fig. 10. 
1921. af McIntosh. Ann. Nat. Hist., ser. 9, vol. viii, p. 308. 
The form appears to be typical in structure, the head and anterior region being 
represented in Plate CXX XV, fig. 16. 
