262 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.21 



foreign growths, such as hydroids, seaweeds, bryozoans and sponges, that, 

 in their natural environment, they are scarcely recognizable as crabs at 

 all. (Holmes) A 60 mm specimen carries a rhizocephalan parasite. 



Depth: 4-74 fathoms. (Rathbun, 1925) Shore to 110 fathoms, Velero 

 III and IV. 



Size and sex: As the Hancock series contains about three times as 

 many specimens of Loxorhynchus crispatus as of L. grandis, the record 

 of growth and development is correspondingly more complete. Young 

 specimens of from 5.4 to 14 mm look much alike. The pre- and post- 

 orbital spines are tipped with a translucent spinule and tend to curve 

 forward. The single hepatic spine is sharper than the same spine on L. 

 grandis, and there are three similar spines evenly spaced along the lateral 

 margin. The anterior corner of the branchial region is sharply angled, 

 and in the indentation between it and the hepatic swelling the similarly 

 rounded pterygostomian region is exposed. While this young fades per- 

 sists to 14 mm and larger, it is possible to determine sex in males of 12.5 

 mm, although the pleopods are only half as long as the abdomen at this 

 stage. Shortly thereafter the large bosses of the carapace become discerni- 

 ble and in specimens of 20 mm and over form a most conspicuous char- 

 acter. As in L. grandis, sexual maturity appears to be achieved late, males 

 of 75 mm showing no signs of enlarging chelipeds or females of 58 mm 

 of egg laying. 



Breeding: The gap in the series between the specimens just mentioned 

 and the measured male and female, 119 and 105 mm respectively, is 

 bridged by an ovigerous female of 62 mm collected in June or July and 

 an 84 mm female, definitely postovigerous, collected in October. 



Remarks: Although the specimen measured above is larger than the 

 largest in the collections of the U. S. National Museum ( U.S.N. M. 

 No. 2193), it is not as large as a 133.5 mm male (M.C.Z. No. 2000) of 

 which measurments are given by Rathbun (1925, p. 201). However, the 

 length of the cheliped of the Hancock specimen exceeds by 28 mm the 

 longest cheliped recorded by Rathbun, which belongs to the National 

 Museum specimen. In very old males the length of the cheliped is con- 

 siderably greater than that of the first pair of walking legs, whereas in 

 Loxorhynchus grandis the first two pairs of ambulatory legs exceed the 

 chelipeds. 



The southern limit of range of the species appears to have been cor- 

 rectly defined by Rathbun, for Velero III collectors found no Loxo- 

 rhynchus crispatus south of San Diego. 



