374 BULLETIN 82, UNITED STATES NATIONAL MUSEUM. 



HATHftOMETKA SABSII. 



Professor Sars gives the period of sexual maturity in the Lofoten Islands as 

 June. He found the j-oungest prebrachial stage at the beginning of July. 



PENTAMETROCRINITS TUBERCULATUS. 



The ovaries of a specimen dredged off southern Japan on October 13, 1896, 

 in 169 fathoms, contained well-developed eggs. 



PENTAMETROCRINUS JAPONICUS. 



Well-developed eggs were found in the ovaries of a specimen dredged off 

 southern Japan on August 23, 1906. 



PENTAMETKOCRINUS VARIANS. 



Eggs apparently of full size were found in the ovaries of specimens dredged 

 off southern Japan between August 13 and October 20, 1906. 



The species which have been found spawning in the different months are 

 as follows: 



January: Coviactinia meridionaUs, Catoptometra ophiura, Antedon mediter- 

 ranea, Coccometra nigrolineata, Leptometra phcdangium. 



February: Comatella nigra, Amphimetra spectabilis, AmpMmetra parilis, 

 * Antedon mediterranean Coccometra hagenii. 



March: Comissa spanoschist^im, Tropiometra picta, Antedon m^diterranea. 



April: Comissia spanoschistum, Tropiometra picta, * Antedon mediterranea. 



May: Cenometra. delicata, Antedon bifida, Antedon mediterranea. Antedon 

 adriatica. 



June: Antedon bifda, Antedon mediterranean Antedon adriatica, Hathrometra 

 sarsii. 



July : Comissia Uttornlis, Antedon bifida, Antedon mediterranea. 



August: Calyptometra lateralis, Antedon mediterranea, Compsometra loveni, 

 Pentametrocrinus japonicus, Penfametrocrinus variant. 



September : Comanthus japonica, Tropiometra macrodiscus, Antedon mediter- 

 ranea, Compsojnetra loveni, Psathyrometra fragilis, Pentametrocrinus varians. 



October: Coinanthus japonica, Antedon mediterranea, Pentametrocrinus tuber- 

 culatus, Pentametrocnniis varinns. 



November: * Antedon mediterranea. 



December: * Antedon mediterranea. 



In the case of Antedon mediterranea the asterisk (*) indicates the months in 

 which the greatest number of egg-bearing females are found. 



In regard to two species, Antedon bifda and Hathrometra sarsii, there seems 

 to be a definite breeding season in the late spring and early siunmer, from May to 

 July. Both these species live in the northeastern Atlantic, on coasts where the 

 water undergoes considerable seasonal change in temperature and in plankton 

 content, and the definiteness of the spawning period is probably connected with 

 this seasonal change. 



