RUDIMENTARY SPINA BIFIDA. 103 



Of the 15 cases (9 male and 6 female) in which the last lumbar vertebra only 

 was involved, and the 5 cases (3 male and 2 female) in which the last lumbar and 

 first sacral vertebra showed defective ossification, only 1 case, and that in the 

 former class, gave any clinical manifestations: 



T.G., female, aged 36 years. Last lumbar bifid; lumbo sacral strain; pain in sciatic nerve. Retro- 

 position of uterus. 



In one instance in the group where the last lumbar showed an irregularity 

 there were clinical manifestations of associated malformations: 



C.T., female, aged 33 years. Two children, 14 and 12 years respectively. Last lumbar irregular; 

 ureteral stricture left, and sacroiliac strain left side. Retro-position of uterus. 



In the dorsal region incomplete posterior vertebral closure is very rare and, 

 like those cases of the upper lumbar vertebrae, are only occasionally reported. In 

 approximately 3,000 dorsal vertebra; seen at the National Museum the condition 

 was not observed in a single instance. Joachimsthal (1895) presents the case of a 

 "Woman with the horse's mane." In this there were evident interruptions in the 

 second to the fifth vertebral arches, with hair 27 cm. long over the site of the defect. 

 In the cervical region, other than with the atlas, a bifid condition of the vertebral 

 arches is likewise rare, only one case being found among 3,500 cervical vertebrae 

 examined at the National Museum. This was in the bones of a Massachusetts 

 Indian (No. 227471), in which the fifth cervical lacked dorsal laminae. Unfortu- 

 nately C 4 of the series was missing, nor were any other vertebra? present. These 

 cervical vertebrae are shown in figure 6. One case was encountered when examining 

 the X-ray plates; in this there were multiple spinal anomalies, and C 7 showed incom- 

 plete dorsal union: 



E.S., male, age 16 yrs. In hospital for osteomyelitis of humerus. Right sided scoliosis in upper 

 dorsal region. Body of D 3 replaced by two triangular wedges on right side and one on 

 left. C 7 showed incomplete dorsal arch. Scoliosis with convexity to left in lumbar region. 



Rauber (1907) cites a case in an adult male skeleton where C 6 showed a bifid 

 condition. The case described by Barclay-Smith (1910) may also be mentioned 

 here: 



Young female Egyptian. Atlas synostosed to occiput. Cz and C 3 fused together; C? interrupted 

 neural arch dorsi-median ; 2 laminae mutually independent, with spinous process sub- 

 divided; 8 cervical vertebra and C 8 showed a small, unilateral cervical rib. L 3 , , 5 and 

 Si showed lateral interruptions to dorsal arch. 



With the atlas the occurrence of a bifid condition of the vertebral arch once 

 more appears as a fairly frequent variation. Here, as in the lumbar region, it is 

 found in the vertebra which, in a freely articulating series, lies next to more rigid 

 structures. Incomplete posterior arch of the atlas was observed in 11 out of 745 

 cases (1.47 per cent). Table 3 gives the incidence in the various groups studied. 

 Two of these were included in a group of 50 cases of Swiss Alpine type, reported to 

 me through the kindness of Dr. Adolf H. Schultz, and which belong to his private 

 collection at Zurich. In addition to these 1 1 cases there are in Dr. Hrdlicka's exhibit 



