ECIIINOIUKA. II. loj 



strony^ly serrate at the edge (PI. XV. Fig. 35). The sphseridi;c do not present prominent features; they 

 occur (in tlie larger specimens) also at tlie large tul)efeet at the posterior end of the test. 



It is an important fact that even in llie smallest specimens there is no trace of a latero-anal 

 fasciole, so that it may be regarded as jjroved that this fasciole is ne\-er found in IJciniastcr — a very 

 characteristic difference from the young of the genus Aba/us. In the young jlhahts there is a large 

 fasciole enclosing both tlie apical s\stem and the anal area; a transverse band then develops between 

 the apical and anal area, and the part of the original fasciole behind the transverse band thus 

 becomes the latero-aual fasciole, whereas the anterior part of the original fasciole in connection with 

 tlie transverse band forms the peripetalous fasciole. In Ilciniastcr the anal area is never intrafasciolar.' 

 In the specimen of 3'"'" the peripetalous fasciole is already distinct (Fig. 17), and at a comparatively 

 large distance from the anal area. It is very small and in the anterior j)etal only one tube-foot is 

 distinct — and by no means very large — and two more are about to appear. In specimens a little larger 

 the peripetalous fasciole is very prominent, Ijroad, but still enclosing only a very small space (I'l. I\'. 

 Fig. 10); upon the whole the fasciole is comparativel\- much broader in the smaller specimens. Tlie 

 odd anterior ambulacrum develops early, thus at a size of 5 — 6'"'" already 4—5 rather large tube-feet 

 are formed. The paired petals are not developed till later on. In a specimen of 10""" length I find in 

 the antero-lateral petals 5 pairs of pores in each series, but of the postero-lateral petals no trace is 

 seen as yet. In a specimen 12""" in length I find 2 pairs of pores in each series in the postero-lateral 

 petals. The smallest sjiecinieii in which I have found the genital pores developed was 14""" long. 



This species was taken by the tingolf at the following stations: 



St 24 (63° 06' Lat. N. 56° 00' Long. W. 1199 fathoms 2^4 C. Bottom temp.) i specimen. 



— 39 (62° 00' — 22° 38' — 



— 40 (62° 00' — 21° 36' — 



— 63 (62° 40' — 19° 05' — 



— 67 (61° 30' — 22° 30' — 



— 68 (62° 06' — 22° 30' — 



— 69 (62'= 40' — 22° 17' — 



Unfortunately several of the specimens were in a more or less broken condition. — The spe- 

 cies was further taken by the Thor at 62° 57' Lat. N. 19^ 58' Long. W. 975 M. (1903) and by JMicliael 

 Sars», 61° 40' Lat. N. 3" 11' Long. E. 220 fathoms, 6°3 bottom temperature (Ad. Jensen. 1902). The latter 

 locality (the Shetland-Norway ridge) is rather surprising and ma}- indicate the j^ossibility of the species 

 occurring along Norway. (Com p. Ecliiiins ^ilrxaiidri). 



The geographical distribution of this species is thus the Northern Atlantic, from the I)a\-is 

 vStrait to the Caribbean Sea and from vSouth of Iceland to the Azores. It belongs to the warm 



■ This feature, combined with the ethinophract apical systein. the 4 genital pores, the difference in the pedicellari.-e 

 (evidently the least important character) and the ver}' great difference in the whole shape and appearance, proves beyond 

 doubt that Loven was quite right in maintaining that the antarctic forms: Abatus cavcrnostis etc. cannot be referred to the 

 genus Hemiastey, as done by Professor Agassiz. < An extraneous form like this, if suffered to remain in the otherwise homo- 

 geneous group of true Hemiasters, is sure to vitiate its integrity, and the mixed assemblage thus set up for a natural genus, 

 if taken on trust, cannot fail to mislead when the question is to trace out comparatively its former geological and actual 

 geographical distribution >. iLoven. On Pourtalesia. p. 73). In his last work, <The Panamic Deep-Sea Echini , .\gassiz 

 recognizes the correctness of Loven's views, while Doderlein (Echinoidea d. deutsch. Tiefsee-Exp.) still refers the antarctic 

 forms to Hetniaslei-, without entering upon the question, however. This question will be treated at more length in my Re- 

 ports on the Echinoidea of the German and Swedish South-Polar Expeditions). 



