This paper presents two proposals to improve the text of an important passage in Manilius’ Astronomica, 1.456–68, in which the poet explains natura's rationale for arranging the stars in such a way as to create only a partial, rather than a full, representation of the constellation figures. The text of line 464 is repunctuated in order to give proper emphasis to natura's parsimonious disposition of the stars. Scholars have noted that the sentence atque ignibus ignes | respondent in 466–7 is not consistent with the poet's account of how the constellation figures were delineated nor with what an observer sees in the heavens. The conjecture insignibus (neuter plural), for the transmitted atque ignibus in line 466, is offered to indicate that it is the distinctive features (insignia) of the figures to which specific stars correspond and by means of which the figures are described. Attention is also drawn to a striking paronomasia in 466–7, designat … insignibus ignes, which creates a meaningful phonetic constellation of celestial fire (ignis), sign (signum) and insigne (distinctive feature) and thus provides evidence, on the linguistic level, of natura's providentia.

Housekeeping genes (HKG) are paramount for accurate gene expression analysis during preimplantation development. Markedly, quantitative reverse transcription polymerase chain reaction (RT-qPCR) in ovine embryos currently lacks HKGs. Therefore, we tested 11 HKGs for RT-qPCR normalization during ovine parthenogenetic preimplantation development. Seven HKGs reached the qPCR efficiency threshold (97.20–105.96%), with correlation coefficients ranging from −0.922 to −0.998 and slopes from −3.22 to −3.59. GeNorm ranked glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and TATA-binding protein (TBP) as the best HKG pair, while H3 histone, family 3A (H3F3A) was the third HKG. Relative gene expression was measured for zinc finger protein X-linked (ZFX) and developmental pluripotency-associated 3 (DPPA3) transcripts during ovine parthenogenetic preimplantation development. ZFX did not show any transcript abundance fluctuation among oocytes, cleavage-stage embryos, and morulae. DPPA3 transcript abundance was also similar among all developmental stages, therefore suggesting that it may not display a maternal gene expression profile. In silico analysis of ovine DPPA3 mRNA and protein showed high conservation to bovine orthologues. However, DPPA3 orthologues differed in regulatory motifs. In conclusion, GAPDH, TBP and H3F3A are stable HKGs in ovine parthenogenetic embryos and allow accurate RT-qPCR-based gene expression analysis.