Second report of an apparently new type of primordial dwarfism characterized by severe intrauterine and postnatal growth retardation, striking craniofacial deformities and a peculiar osteochondrodysplasia. The major clinical findings are microcephaly, hypotrichosis, bulging eyes, prominent nose, micrognathia and short extremities. The osteochondrodysplasia is characterized by short and bowed humeri and femora with absent ossification of the femoral necks, small and dysplastic iliac wings, strikingly retarded ossification of the epiphyses and shortened metacarpal I and middle phalanges II-V. Possible this condition is caused by the homozygous state of mutant gene. The brachymelic type of primordial dwarfism differs from other forms of primordial dwarfism (particularly from case I of Seckel) by its skeletal abnormalities. The cases described by Seckel (and sometimes referred to as Seckel or bird-headed dwarfism) are heterogenous: Seckel dwarfism apparently does not exist as a nosologic entity.