FISHES OF FAMILY BLENNIIDAE 53 



Vertebeal column. — The number of vertebrae in blenniids varies 

 from 29 (rarely 28) in Stanulus to 134 in Xiphasia. Only in some 

 genera of the Nemophidinae does the number of vertebrae exceed 

 45. The number of precaudal vertebrae — i.e., anterior to the first 

 vertebra with a well-developed haemal spine; most often the transition 

 from precaudal to caudal vertebrae is abrupt, from no haemal spine to 

 a well-developed one — ranges from 9 to 12 in the Blenniinae and from 

 11 to 16 in the Nemophidinae. By far the most common number is 

 10 (secondarily 11) in the Blenniinae and 13-16 in the Nemophidinae. 

 A variation of plus or minus one precaudal vertebra from the modal 

 number is a rarity for a specimen of any species of the Blenniinae 

 and is only slightly more common in the Nemophidinae. 



The precaudal vertebrae bearing parapophysial stays (always those 

 vertebrae just anterior to the first caudal vertebra) varies from none 

 to three in the Blenniinae and to jBve in the Nemophidinae. A varia- 

 tion of plus or minus one from the modal number is common for 

 any specimen of a given species. 



In the Blenniinae, except the Omobranchini, the neural arch of the 

 first vertebra, with rare individual variants, is complete, but lacks a 

 neural spine. The first well-developed neural spine usually appears on 

 the third vertebra (on the fourth vertebra in the single specimen of 

 Istiblennius coronatus examined). Infrequently there is a low, weak 

 neural spine on the second, and less commonly on the first, vertebra. 

 In the Omobranchini a weU-developed neural spine frequently occurs 

 on the second vertebra. In the Nemophidinae the two sides of the 

 first and/or second neural arch fail to meet dorsally in Runula, Dasson, 

 Blennechis, and Aspidontus. The first well-developed neural spine may 

 be on the second or third vertebra. 



In the Blenniinae, except the Omobranchini, many species and 

 genera possess a well-developed process (not labeled in fig. 11) on 

 each side of the base of the neural arches of the third, fourth, or fifth 

 vertebra (just the first two or all three of these vertebrae). Strong 

 hgaments extend from these processes to the proximal ends of the 

 associated epipleurals. In the Omobranchini, the processes are always 

 present and occur on the neural arches of the second or third to fifth 

 through tenth vertebrae, depending on genus and species. In the Ne- 

 mophidinae, except Xiphasia, where apparently they are absent, 

 the processes exist on the neural arches of the third to fifth through 

 tenth vertebrae. The processes in all blenniids are sometimes not 

 noticeable in small or young specimens. 



In all the blenniids there is a tendency for the parapophyses of the 

 middle precaudal vertebrae to develop into winglike processes that 

 overlap and attach Hgamentously to the next vertebra anteriorly. This 

 development reaches its extreme in Xiphasia, where in many respects 

 they superficially resemble the condition in the f ossU elopoid Lamino- 



